07:57 Good morning and welcome to day three of AUTOSPORT Live's coverage of Barcelona Formula 1 testing.

07:58 We've now passed the halfway point of the 2013 F1 build-up already.

07:58 It may seem like no time at all since we first squinted at a Lotus launch car, but we're now familiar with all 11 2013 machines and have had six of the 12 days of testing.

08:00 The big talking point today will be the return of Adrian Sutil, last seen in an F1 car in the 2011 Brazilian GP and now auditioning for the vacant seat at former team Force India.

08:00 Nico Rosberg is back in the Mercedes, and he is first to set out on track as the green light comes on.

08:00 Jean-Eric Vergne comes out next in the Toro Rosso.

08:00 Followed by Max Chilton's Marussia.

08:01 Weather feels similar in temperature to Wednesday morning - i.e. cold - but after yesterday's sunshine it's a cloudy and slightly foggy day.

08:01 Showers are forecast for Friday, putting more emphasis on gaining mileage today.

08:01 Giedo van der Garde's Caterham hits the track.

08:03 Valtteri Bottas walks up to AUTOSPORT Live to remind us that #BOTTAS should always, always be in massive capitals. He said it was important to deliver that message in person.

08:04 He indicated just how massive with outspread arms. Sadly the AUTOSPORT Live technical system won't allow his requested word girth. #BOTTAS

08:05 When he came in as an AUTOSPORT Live guest at Jerez, #BOTTAS also requested that MAXIMUM ATTACK should be in the style guide.

08:05 Markku Alen, Juha Kankkunen, Mika Hakkinen and Marcus Gronholm wouldn't complain we're sure.

08:06 Rosberg puts a time of 2m09s and then 1m54.056s as he stays out to go straight into constant speed aero tests.

08:07 Fernando Alonso, Jean-Eric Vergne, Mark Webber, Adrian Sutil, Nico Hulkenberg and Romain Grosjean have also done installation laps. Only one yet to emerge is Jenson Button's McLaren.

08:08 In just over 90 minutes' time, Sauber rookie Esteban Gutierrez will be joining AUTOSPORT Live to answer your questions. Email live@autosport.com or tweet with the hashtag #autosportlive

08:15 Meanwhile Gutierrez's Sauber team-mate Nico Hulkenberg comes out on track to start a second run.

08:16 Everyone has now done at least one installation lap, with Rosberg and Grosjean racking up four each, but Rosberg's aero-test-cruising 1m54s is the only time so far.

08:17 Hulkenberg could be on a flying lap now, although his Sauber only sounded moderately purposeful (definitely lower case) not MAXIMUM ATTACK past the pits.

08:17 Vergne is also on track.

08:20 Still no more times, and now it's Chilton alone on track.

08:21 Now joined by van der Garde for what could be a thrilling head to head between F1's tail-end squabblers.

08:21 Marussia plans via @marussia_f1team:

"It's a bit cold to start with so we'll be doing more starts and working on other procedures, then building up to some aero work"

08:22 Anyone following television's @willbuxton on Twitter should know that when he tweets about underwhelming GP3 liveries, his sadness is real.

08:23 He's sat opposite us looking genuinely gutted.

08:23 Chilton sets the fastest time so far with a 1m35.802s.

08:25 Van der Garde deposes Chilton, but only for moments before Webber hits the front on a 1m27.385s.

08:26 Webber goes faster again on a 1m26.569s.

08:36 Maldonado begins his flying laps with a 1m26.807s to go second, 0.2s behind Webber.

08:36 Now Maldonado steals the top spot away with a 1m25.671s.

08:38 (When there's lull, we'll tell you about @eddstrawF1's dream last night. Not for ego reasons, but because many motorsport fans reading might go "yes, that would be cool if it was real")

08:38 No lull right now though, we have Maldonado, Chilton, Rosberg, Alonso and Sutil in action on the circuit.

08:38 Sutil comes back in.

08:39 Maldonado follows his 1m25.6s with a 1m26.1s.

08:39 Maldonado hands over to #BOTTAS for an afternoon of MAXIMUM ATTACK (and dutiful data gathering) later

08:40 Now Maldonado comes back into the pits. He featured in @eddstrawF1's dream.

08:41 About an hour left to get your questions in for Esteban Gutierrez. Email live@autosport.com or tweet with the hashtag #AUTOSPORTLive

08:42 Grosjean joins the times with a 1m34.149s.

08:45 Also in @eddstrawF1's dream were an IndyCar title contender and a man who took a best finish of 11th in his sole British Touring Car season.

08:45 Grosjean improves to a 1m31.001s, going third, although times still mean little.

08:46 Webber's pace is more representative, as he does a 1m26.346s to trim Maldonado's lead to 0.6s.

08:47 New fastest times in the first two sectors for Webber so expect a change at the top.

08:47 Not quite, Webber is slower in the final sector and does a 1m26.145s.

08:49 Webber continues round with a 1m26.533s. Just the two Red Bull teams on track now with Vergne also in action.

08:50 The Red Bull is using medium tyres. Webber continues round in 1m27.1s.

08:53 Webber brings the Red Bull in, pops behind the secrecy screens, revs hard then switches the engine off.

08:53 Maldonado sets off onto an empty track.

08:54 This is an ideal lull to summarise @eddstrawf1's dream.

08:56 After a late night conversation about A1GP in the AUTOSPORT triple-height bunkbed, Edd dreamed the nation-versus-nation series was revived. With Will Power and Mark Webber sharing the Team Australia car, Maldonado driving for Team Colombia (err...?), sometime works Proton BTCC driver Farique Hairuman driving for Malaysia, and the season starting at Sentul in Indonesia.

08:56 Back in the real world of F1, Maldonado sets a new fastest time of 1m22.675s.

08:59 That was a single-lap burst from Maldonado on soft tyres.

09:01 Television's @willbuxton is still sad about GP2 and GP3 liveries. Even his scarf looks downcast.

09:01 We've all agreed there would be nothing wrong with a beige racing car.

09:02 Just Grosjean on track now.

09:02 Lap tally for the first hour: Maldonado 9, Webber 13, Grosjean 10, van der Garde 10, Chilton 6, Rosberg 8, Vergne 12, Alonso 6, Sutil 5, Button 4, Hulkenberg 4.

09:02 Alonso comes back out in the Ferrari.

09:05 Pictures from the morning starting to filter in, here's Sutil back in a Force India.

09:06 Alonso up to second place on a 1m22.998s.

09:07 The Ferrari is running soft tyres, and goes up to a 1m25s on its second flying lap.

09:09 Half an hour left to get your questions in for Esteban Gutierrez. Email live@autosport.com or use the hashtag #AUTOSPORTLive.

09:12 On track now, Vergne and Maldonado.

09:13 Webber rejoins the circuit as Maldonado gets up to speed with a 1m23.1s.

09:16 Maldonado was on another single flying lap, using super-soft tyres - a rare choice for this week.

09:16 Webber improves to a 1m23.406s. He's out on medium tyres.

09:25 A string of recent improvements among the group of cars still running either heavier or on purely evaluation programmes put van der Garde, Hulkenberg and Vergne fourth, fifth and sixth.

09:27 Lewis Hamilton isn't driving today, so he's walking dog Roscoe in paddock.

09:29 One of AUTOSPORT Live's most geeky teenage race-fan habits in the mid-1990s was compiling a spreadsheet of racing drivers' pets...

09:29 It even included Gilles Villeneuve's dogs.

09:29 As is clear from that digression, the track has gone quiet bar Chilton on a slow lap.

09:30 Chilton comes back in, so the track is empty.

09:30 Everyone has set a time bar Sutil and Button.

09:30 Chilton just paused at the Marussia pit and now resumes running, commencing a 10th lap.

09:34 Highest lap count so far is Vergne on 20, though Webber is catching up as he sets out to begin his 19th.

09:39 Webber does a single lap on medium tyres then pits.

09:40 Vergne improves to 1m25.577s in fourth.

09:41 Improvement from van der Garde, who does a 1m27.344s in fifth place.

09:44 Grosjean jumps up to fourth on a 1m24.376s, 1.7s off Maldonado.

09:45 Alonso grabs the top spot from Maldonado with a 1m22.510s.

09:46 The Ferrari is out on soft tyres and its second lap of the run is a 1m24.785s.

09:46 Some debate over whether Lewis Hamilton's dog should appear on the homepage. This gets an editorial veto because Roscoe is not a greyhound.

09:47 Alonso brings his run to an end and pits after two flying laps.

09:50 A quiet track now with all 11 teams back in the pits, so a good time for a recap.

09:51 Alonso is fastest on a 1m22.510s, 0.185s up on Maldonado, then Webber, Grosjean, Vergne, Hulkenberg, van der Garde, Chilton, Rosberg.

09:51 No times yet from Sutil or Button, though Sutil has done 13 in/out laps.

09:54 Van der Garde has been busiest with 24 laps, then Webber on 22 and Grosjean on 21.

09:54 Rest of the pack: Alonso 18, Maldonado 12, Hulkenberg 14, Chilton, 10, Button 6.

09:54 Webber leaves the pits in the Red Bull.

09:56 Maldonado and Hulkenberg rejoin the track too.

09:56 A big lock-up into Turn 1 as Webber commences the first flying lap of this outing.

10:00 Webber did a single 1m40s lap, then pitted.

10:00 Hulkenberg is out now on hard tyres, lapping in mid-1m28s.

10:03 Marussia shows that traffic cones still have a role in modern F1. Even Red Bull was using them as pit markers yesterday.

10:05 Alonso takes the fastest time away from Maldonado again with a 1m22.301s.

10:06 That lap from Alonso came on soft tyres. Next time around he does a 1m24.1s.

10:09 Button starts his flying laps for the day with a 1m24.530s, putting the McLaren fifth.

10:13 Sutil's comeback commences in earnest with a 1m25.936s to go seventh.

10:14 Sutil improves to a 1m24.890s.

10:16 Rosberg sets off again after a long time in the pits. Mercedes had been doing data-logging work and needed to remove a lot of measuring devices.

10:16 Rosberg immediately moves forward into fourth with a 1m23.153s.

10:17 Sutil stays out, doing a 1m25s then a 1m27s.

10:20 While Sutil tries to prove to Force India that he's the right man for the job, Paul di Resta says he's not fussed who his team-mate is.

10:22 Rosberg did a slow lap, then got back up to speed with a 1m24.933s. He's on medium tyres.

10:23 Banner Watch news: the de la Rosa and Kubica fans are still here, Kimi's crowd has gone as Grosjean's on Lotus duty, and there is a man with a South African flag.

10:24 But there's also a banner that starts with 'Red Bull' and ends with 'COJONES!!!'

10:24 What it says in its ruffled middle isn't clear from the press room windows, sadly.

10:25 Maldonado is now the only man on track.

10:26 Vergne comes out as well.

10:30 Vergne improves to a 1m23.983s lap in fifth position.

10:31 Alonso, Maldonado, Vergne, Grosjean and van der Garde are now on the circuit.

10:31 Alonso raises the stakes by lapping in 1m21.192s, taking him 0.483s clear of Maldonado.

10:33 Alonso is on soft tyres, and his next lap past is a 1m24.4s.

10:35 Rosberg jumps to second with a 1m22.627s.

10:35 We're with Esteban Gutierrez and ready to kick off our Live chat. The first question comes from Anna, who asks:

You have a nickname (as I know) "Stevo" - where did this nickname come from?

Esteban Guteirrez: 'Well, this nickname is from very close friends back in Mexico. When I was young they used to call me Stevo instead of Esteban. Not a lot of people use it, only my close friends."

10:36 Hulkenberg also improves, going 0.6s faster than before to take fifth for Sauber on a 1m23.849s.

10:39 Sutil goes fifth on a 1m23.641s.

10:41 I'm no expert on GP2 but noticed in 2012 that it can be very exciting, almost wild at times. Some drivers clearly can adapt straight away to the perceived differences required in F1 but others may struggle. Do you feel there is a difference in the two?
Mr Nelson

Gutierrez: "I think that the main change between GP2 and Formula 1 is from a psychological point of view. There is more media pressure, you are exposed basically to the whole world from a media point of view. And of course it's the top level so the result is the only thing that counts.

"At some point you consider the rookies coming in need some time to prepare and to adapt to the situation, but at the end of the day everyone expects the best results from the drivers. I think in F1 lately it has been every exciting races too with the characteristics of the Pirelli tyres, and now they seem more drastic so it will keep the races exciting and quite similar to GP2 probably."

10:42 Rosberg's jump to second came at the start of a relatively long run on medium tyres. He backed right off to a 1m40s next time around and has been in 1m24s and 1m25s since.

10:43 Button gets the McLaren up to sixth on a 1m23.839s.

10:44 Esteban, there is little testing for new drivers at the moment, do you think you will be fully prepared for Melbourne?
Tom Conway

Gutierrez: "I’m doing my best, but yes, it’s a very short time, only six days in total. It’s not easy of course because as a rookie you need a lot of laps and seat time to adapt, but this is what we have and what I’m trying to get the most out of. Basically it’s my only focus at the moment. We will see at Melbourne. It will be my first experience of a Formula 1 race."

10:48 How's it going with the new race engineer? Pay attention that he's my brother!
Federico Nenci

Gutierrez: "Haha. Well I feel very comfortable with him. He is very analytical in general and he considers where, as a rookie, I can get up to speed. He wants me to get there as quickly as possible, which is the same goal I have. At the same time he is adapting the team's development programme without compromising it, to combine with my own preparation. He's showed me some exercises to help me get up to speed quickly. The work with him is going very well, I am very comfortable."

10:50 Alonso trims a few hundredths off his benchmark with a 1m22.144s.

10:50 Hulkenberg also stepped his pace up with a 1m23.397s.

10:53 Alonso's lap again came with a quick run on soft tyres, with the pace then going up by a few seconds after his best time.

10:54 Vergne and Maldonado are the only drivers on track now, both lapping in mid-1m28s to low-1m29s.

10:56 Had a reader request for an aerodynamic/technical comparison explaining why a greyhound will outpace Lewis Hamilton's dog.

10:56 Might hunt for a suitable picture in the lunchbreak.

10:57 How did you come up with such a sexy helmet design?
Luke from Australia

Gutierrez: "Aha. Well, I feel proud of the yellow and blue! It's a nice combination of colours, and you can see the helmet shining against the car. This is something I wanted to achieve so my followers can recognise who is driving the car straightaway. I helped in the design, and I think we achieved this."

10:57 Maldonado's pace goes up to 1m30s as he continues on a long medium tyre run.

11:00 Esteban, are you confident of beating Nico Hulkenberg in qualifying this year?
Adita

Gutierrez: "My goal is to be at his level. I am going to take it step by step, because he has three years of experience in Formula 1 and I cannot expect straightaway to beat him. But he is a great reference for me, I know that. I am going to work on being at his level this year."

11:01 Grosjean comes out and does a 1m22.332s to take second, just 0.188s behind Alonso.

11:02 Grosjean is running on soft tyres. He backs off to 1m36s on his second lap.

11:05 Chilton sets Marussia's first quick lap of the day. He's still last on a 1m28.520s.

11:05 Many Formula 1 fans were disappointed by Sauber's decision and F1's failure to keep Kamui Kobayashi in the sport. How do you feel you will able to cope with comparisons to the man who you have re placed, especially with the debate around "pay drivers" continuing?
Tom, Tonbridge UK

Gutierrez: "I think Kamui was a great driver. I had a great relationship with him actually. I really don't have this in mind though, I don't think about me replacing him or not. It is just different stages in life – new drivers come in.

"Of course it doesn't feel the best to say OK I'm here in place of Kamui because he was a good friend of mine, but things happen. I'm here now and I'm going to do my best to make the most of the opportunity, because I know how many people want to be in this position."

11:05 A 0.042s gain for Webber as he does a 1m23.024s.

11:07 Webber stays in low 1m23s on lap two of his run. He's using medium tyres.

11:07 Which track are you most looking forward to driving on the F1 Calendar?
@Jdixoncfc

Gutierrez: "Suzuka. It's a track that I really want to get to know. It has a lot of fast corners, it is very technical, so I'm really looking forward to that. Second? Austin."

11:08 A group of circuit guests are being shown the media centre while on their tour. Sadly they are denied the chance to be photographed with @eddstrawF1 as he's currently in the paddock.

11:08 There's time for just two more questions in our AUTOSPORT Live chat with Esteban Gutierrez - thanks for everything that has already been sent in.

11:08 Just the two flying laps from Webber and now he's back in.

11:12 What are the five characteristics that describe the driver Gutierrez best? What would you like to change or improve?
Daniel (the psycho-profiler) from Gibswil

Gutierrez: "Haha. This is difficult to describe yourself! At least my aim is to be the most professional possible, and develop myself as a driver and a person with all the experiences I will be living. As well, I will try to always be disciplined and to be sure I am always doing my best because this is the way I can generate confidence in myself."

11:12 Hulkenberg jumps up to second with a 1m22.160s, a mere 0.016s off Alonso's pace.

11:13 Our final question for Esteban comes from Joe Padgett, who asks:

How are you expecting to feel just moments before the lights go out at Melbourne? Will you be nervous or will it just be the same as the start of any other race?

Gutierrez: "My aim is to feel like it is the start of any other race. I think that is important in order to keep the focus, and not have other things distracting me from the moment.

"That will be quite a challenge, because it is Formula 1, the top level, and I will be about to race the best drivers in the world. It's going to be a very special moment, but I need to keep myself isolated from all these feelings and emotions."

11:14 Hulkenberg's burst of pace came on a short run on soft tyres. He now pits again.

11:16 Button does a 1m22.840s to cement sixth place in the McLaren.

11:16 A massive thanks to Gutierrez and Sauber for today's Live chat, and for all the questions we had.

It's just over three weeks until he does make his F1 debut in Melbourne. Until then you can follow his testing progress through AUTOSPORT and the man himself on Twitter.

11:18 Just a quick run for Button on hard tyres. He's now back in the pits.

11:18 Alonso has come out on soft tyres is fastest so far in the middle sector.

11:19 Sure enough, Alonso sets a new fastest time with a 1m21.875s.

11:25 Grosjean is back out and sets a new fastest time in sector one.

11:26 Grosjean, running on softs, improves his time but not his position. A 1m22.188s keeps him third.

11:27 Chilton and van der Garde are running together on track, and are well-matched on times too. Chilton trims his time to a 1m27.791s to edge ahead of the Caterham by 0.136s.

11:28 Hulkenberg's sector times hinted at an improvement as he does another run on softs.

11:29 But the Sauber came up behind Webber's heavier Red Bull in the final sector and lost a tenth or so.

11:30 Sutil improves his pace to a 1m22.877s.

11:33 AUTOSPORT will be talking to Sutil about his prospects of landing the Force India drive at the end of the day.

11:34 As tempting as it will be to compare Sutil and Jules Bianchi's lap times head to head, raw pace is unlikely to be the clincher.

11:34 As Sutil's varied programme - starting with over an hour of evaluation runs - showed today, Force India is seeing how its candidates fit in to all aspects of the team.

11:35 Plus with showers forecast tomorrow, Bianchi might not have chance to equal whatever times Sutil ends today on.

11:37 Vergne finds 0.6s to do a 1m23.366s in ninth place.

11:38 Another soft-tyre run for Alonso starts with a 1m22.041s, two tenths off his best but faster than anyone else has gone today.

11:42 Chilton improves to 1m26.416s to pull Marussia a second clear of van der Garde.

11:44 Yesterday, Dries Doorne asked AUTOSPORT Live if the teams brought catering facilities to tests, and if that's where AUTOSPORT ate.

11:45 Caterham and Lotus are the only teams with their full-spec paddock hospitality and motorhome presence here. They'll probably leave them after the tests as they are not used for flyaway races and won't be seen again until the grand prix at Barcelona.

11:46 The other teams have all got smaller, more basic facilities than they would have at grands prix.

11:46 But they are still making sure their drivers are fed. #BOTTAS has yet to join us in a McDonalds queue.

11:47 And yes, sometimes teams do generously feed AUTOSPORT Live too. Failing that, we stuff as much of the hotel breakfast selection into our bags as we physically can, then make that last.

11:49 As we head into the final 10 minutes of the morning session, Hulkenberg, Grosjean, Button, Vergne and Chilton are on track.

11:53 Into the final seven minutes of the day. Chilton, Button, Grosjean and Vergne head in almost in unison.

11:53 Which means this morning's pacesetter Fernando Alonso is our only man out on track right now.

11:54 Alonso has 47 laps under his belt this morning. Only Pastor Maldonado (79) and Jean-Eric Vergne (66) have managed more.

11:56 Another low 1m22s effort from Alonso, faster than everyone but Hulkenberg and Grosjean. His next lap is slower though, to the tune of around three seconds.

11:58 Two-lap run on softs finished, Alonso heads in and then straight back out. He has Grosjean and Rosberg for company as we near the morning's end.

12:00 Alonso repeats the in-out trick, getting out just before the chequered flag waves.

12:01 So that's it for the third morning here at Barcelona. Fernando Alonso leads the way with a 1m21.875s, just over a quarter of a second clear of the field.

12:02 The AUTOSPORT Live team is off to scavenge lunch, or failing that wolf down this morning's stashed breakfast items.

12:04 In the meantime you can read our morning report here. Join us at 13.00 GMT for the penultimate afternoon from the second pre-season test of 2013.

13:00 No need to set an alarm at Barcelona - the shriek of V8s all along the pitlane is all the reminder we need that we're about to get underway again.

13:01 And we're green. Nico Rosberg wastes to time and it straight out.

13:04 Rosberg puts a 1m24.728s on the board to start us off this afternoon.

13:07 AUTOSPORT Live didn't manage to eat over the lunch break, but food has just arrived courtesy of TV man (and now slight hero) Will Buxton.

13:09 Multi-tasking has never been an issue though. Nico Rosberg heads by for his fourth lap on mediums. His run so far is:

1m24.728s
1m23.930s
1m24.275s
1m24.574s

13:12 Rosberg adds just one more lap, a mid-1m25s, before he comes in and we're quiet once again.

13:13 Well, except for the now-open fruit machine convention (we're being serious) in the closed-off section of the media centre. If only they had the old Daytona USA arcade...

13:17 Or Sega Rally, as another corner of the media centre suggests.

13:18 @Lotus_F1Team: "Plan for the afternoon; some aero work then a race distance simulation. You won't see any super quick times."

13:20 Sutil, Hulkenberg and Rosberg all out now.

13:22 Rosberg improves by all of 16 thousandths of a second. He stays fourth for now.

13:23 Van der Garde, Bottas and Grosjean all head out now.

13:24 A strong out-lap for Bottas that - green in sectors two and three and new bests through all three speed traps.

(Partly to use our new icons, it's worth pointing out the Finn has come in for Pastor Maldonado this afternoon).

13:27 Bottas's first flyer of the day is a 1m25.719s, which sends him 10th overall. Van der Garde improves at the same time to a 1m26.329s.

13:30 We're not sure how this works...van der Garde sets new bests in all three sectors but comes round in a 1m27s, just under one second off his actual best.

13:31 And as we ponder that, everyone heads into the pits. The silence doesn't last long though - moments after Grosjean boxes, Jean-Eric Vergne heads out for Toro Rosso.

13:34 Interviews and paddock wanderings provisionally completed, Edd Straw is with us for the afternoon - which means "Ask the Edd" is back in business. If you have any questions about testing - be it current form, rules and regulations or expectations for the year ahead - send them in to live@autosport.com.

13:36 @Pastormaldo: "Great test this morning, I finished for today... tomorrow in the car again!"

13:37 Just after Vergne begins his 70th tour of the day he suddenly has company, in the shape of Fernando Alonso, Nico Rosberg and Nico Hulkenberg.

13:44 Relatively short runs for Alonso and Vergne, who both pit. Rosberg, Bottas and Hulkenberg and now Sutil out on circuit.

13:45 Bottas jumps up into sixth overall with a 1m22.826s. His second effort is almost exactly one second slower.

13:46 Plenty of interest in who is fastest in each sector. This morning's pacesetter Fernando Alonso found most of his gains in the middle sector, where he's fastest overall. Grosjean tops the first split, while Hulkenberg is fastest in the third.

13:48 Alonso is however fastest in all but one of the speed traps - the first, in which Adrian Sutil's recorded 282.0km/h tops the charts.

13:53 @Lotus_F1Team: "Car nearly ready for next run, just have to re-gas the aircon and change the CD autochanger selection."

13:53 Grosjean is indeed out, and we'll be keeping an eye on this given Lotus's earlier promise of attempting a full race simulation. He opens up with two mid 1m31s.

13:59 Grosjean, incidentally, has started this run on the medium compound. He has Bottas, Alonso and now Button for company.

14:00 We've had some great questions for "Ask the Edd" so far. When he's finished being angry at his computer screen, he'll start responding.

14:02 Grosjean pits for the first time. A quick change onto hards and he's back underway.

14:05 @Marussia_F1Team: "We are completing a pre-planned suspension change and Max will rejoin the track in around 20 mins to conduct set-up work & aero measurement."

14:08 Aaron has the privilege (of sorts) of opening this afternoon's chat with our F1 Editor Edd Straw.

How does Nico Rosberg really compare with Lewis Hamilton? Can we expect a good rivalry?

Edd Straw: "That's one of the questions that only this year can truly answer. Hamilton is a proven performer and even his rivals recognise that there's nobody faster over a single lap in F1.

"Rosberg has the advantage of having been in the team for three years already, but for all his qualities he hasn't been able to show that he's quite in the same class. He's fast and has shown he can win from the front, but right now you'd put him down as a very strong number two, albeit one quick enough to put some pressure on.

"For a more in-depth look at the challenge Rosberg faces, click here (subscribers only)."

14:10 Long runs are pretty much the order of the day all along the pitlane.

@OfficialSF1Team: "In the afternoon @NicoHulkenberg is mainly doing long-runs with high fuel loads."

@WilliamsF1Team: "#BOTTAS waits while the team make more set-up changes before he gets into some longer running."

14:13 One man we know is already on a long run is Romain Grosjean. The Lotus man is currently 13 laps into his stint (which has included one stop so far) and is circulating in the low 1m31s.

14:19 Two similarly-themed questions for Edd concerning Marussia and Caterham.

Looking at the testing times I don't see much of an improvement from Marussia or Caterham. Do you expect they will be mixing it with the back of the midfield this year?
Chris Pratt

Edd Straw: "Based on current evidence, no. Testing suggests that the gap is still there and they will be fighting a private battle for 10th and 11th place overall."

Any opinion on whether the 107% rule while be a bigger challenge for Caterham and Marussia this year?
Michael Kohout

Edd Straw: "I'd be surprised. The back-of-the-grid teams always use the quicker tyre in Q1 anyway, which reduces the challenge, and there's no reason to think that they will be particularly close to the 107 per cent cutoff."

14:23 20 laps in, Grosjean stops for a second time.

14:26 As we try and keep track of a growing number of large runs, conversation has turned to the use of 3D filming and how the final test at Barcelona could look.

14:27 I have read in the past that by analysis of the audio output from an engine it is possible to determine many parameters that would "give the game away" especially if your team is running the same engine. How much of this analysis goes on and how realistic is the "phoney wars" label?
Barry Dench


Edd Straw: "Some teams do this kind of thing and it's valuable data to get an idea of where the rest are. However, that in itself relies on assumptions about what programme the cars are running, how hard drivers are really pushing etc.

"There's also the fact that knowing how far ahead or behind you are makes little odds as at this time of year, teams are trying to put every little bit of improvement they possibly can on the car! Analysis of the audio output of the engine, speed trap figures, trackside observations and the like can given an idea of where the car appears to be, but given the huge variables involved and the tightness of the competitive spread, it's only a guide."

14:31 @clubforce: "What better way for @Jules_Bianchi to wait for his turn in the car tomorrow? You guessed it, photoshoots."

14:33 Not the smoothest of getaways from the Red Bull pitbox, but Mark Webber is not out on track.

14:34 In other news, AUTOSPORT Live's lap chart has already become ridiculously complicated. This could take some deciphering tonight.

14:35 There's something we haven't seen in a while - a bit of green on the timesheets as Max Chilton improves to a 1m25.690s.

14:38 The Marussia man almost improves next time round, but personal bests in the first two splits are undone by a slower third sector.

14:40 Should F1 run young/reserve drivers on Monday's after certain races to give them experience as well as giving teams a little extra testing time?
Craig Stevanato

Edd Straw: "My feeling is that there definitely needs to be greater provision for young drivers (and they should be young, for using 30-something test drivers like Gary Paffett is not what the young driver tests are intended for) to get track time. Tests the Monday after a race are appealing, with the teams already there, but the problem with that are the costs involved and the fact that teams are already flaying tired personnel during a packed season.

"Personally, I'd love to see a way to incorporate young driver running into a race weekend, although that raises the possibility of spare cars being used, which is not desirable. To do that, the extra running must be incentivised.

"There's no easy answer to this, but as Red Bull has shown, nurturing young drivers is hugely beneficial."

14:41 Everyone but Rosberg, Maldonado, Vergne and Chilton on track.

14:44 Rosberg had been out on a long run of his own, managing 17 laps on mediums.

14:45 Jean-Eric Vergne heads out on softs.

14:47 Meanwhile Grosjean, on mediums, pits. A brief check and he resumes his race simulation.

On the pitwall (or at least on Twitter) Lotus plays pit stop bingo.

@Lotus_F1Team: "Two fat ladies, lap 88, pit stop time."

14:53 Roger Coleman has asked what the theoretical best time of today is. AUTOSPORT Live can handle that - taking Grosjean's first sector, Alonso's second and Hulkenberg's third, the ultimate best would be a 1m21.695s, not that much faster than Alonso.

15:00 Mark Webber comes round for the 25th lap of his run, while Grosjean is still out and is on lap 45.

15:02 A bit of disruption in the pitlane as the McLaren men were waiting for Button to come in, only for Giedo van der Garde to come through their box en route to the Caterham garage. Having to jump out the way didn't go down too well with some.

15:04 It's not the most typical question we've had, but we liked it (especially as we were given options, that always makes life easier).

If a hungry lion walked into the media centre, what would you do?

A) Run around waving your arms around then leap through the window
B) Feed one of your colleagues to the lion
C) Give the lion a hug
James Smith

Edd Straw: "First, we would report it in AUTOSPORT Live (of course). Second, I would attempt to sell it a subscription to AUTOSPORT Plus. Thirdly, I would ensure that it is not, in fact, Lewis Hamilton's dog. Finally, I would go for option c and try to feed a colleague to them. A photographer, if possible."

15:06 Who would you pick, Bianchi or Sutil?
Amulya Singh

Edd Straw: "There are a lot of reasons for picking Adrian Sutil. He's an experienced, proven performer and you know exactly what you get with him. But I'd go for Bianchi. He's got a lot of ability. There are question marks over his mental strength, but we've seen Sutil's full potential - that of a pretty good, dependable grand prix driver - and Bianchi could be better. It's a higher risk approach, but the potential reward is greater."

15:10 We're now debating whether a lion could gain accreditation for F1 testing. It's been an odd afternoon.

15:13 With everyone on long runs, Nico Rosberg is the fastest man out on circuit. The Mercedes man, on his final afternoon of the second test, is lapping in the mid 1m28s, a pace only Grosjean is matching.

15:13 Or maybe not. Vergne comes round in a 1m23.683s, which is only three tenths slower than his morning best.

15:16 @ToroRossoSpy: "Could this be the final hour of testing this week? Supposed to rain "gatos e perros" tomorrow. That's Spanish for cats and dogs."

Rain was also possible for this afternoon, but has held off so far. Hopefully we can get lucky tomorrow too.

15:17 What do you make of McLaren's testing form? There does not seem to be much in the way of soundbites coming from them. Do you think they are looking in good shape or struggling a bit?
Kevin Pryke

Edd Straw: "All looks pretty good for McLaren. There's little in the way of flashy headline laptimes or snappy soundbites coming from the McLaren camp, but there have been some eye-catching lap times in conditions that are far from optimum.

"The car also looks very honest and true on track. This doesn't mean McLaren is ahead, but it would be a surprise if it wasn't in the mix."

15:22 Fourth pitstop of the run for Grosjean, and he's back out. Pastor Maldonado clocked up 66 laps en route to victory in last year's grand prix here. Grosjean is currently on 60.

15:28 Grosjean is out on mediums, as is Mark Webber who is 44 laps into his own programme. Only Hulkenberg and van der Garde (softs) and Sutil and Rosberg (hards) are on different compounds.

15:31 How high do you rate Grosjean ? Could he outscore Kimi this year? @MT_Louis

Edd Straw: "Grosjean is seriously quick. Quick enough that if he can harness that speed, he can be a world champion.

"He was fast enough to beat Kimi 10-9 in qualifying last year and he has the potential to be the quicker Lotus driver this year. If he can improve in terms of his ability to assess risk and cut out he accidents, his confidence will rebuild and he will take a big stride towards fulfilling that potential. If the mistakes continue, then it's probably time to cut him lose at the end of the year. A clean start to the year is essential."

15:34 Talking of Grosjean, his race simulation has just ended 66 laps, and four pitstops, to the good.

15:35 A dash of purple as Alonso, on his outlap, goes fastest in the third sector speed trap.

15:40 @Lotus_F1Team: "That's our 'race' done, thank you @RGrosjean, you can have a rest now."

15:41 Hi AUTOSPORT. How do you reckon the Ferrari is this year? Last year testing it was said to be nervous under breaking and lack grip during cornering?
Carlos from Norway

Edd Straw: "We can say for certain that the car is far better than it was at this stage last year. In 2012, watching the Ferrari drivers trying to haul the car from the exit of Turn 2 and into the long right-hander at Turn 3 was painful at times, but now it's a much more well-balanced car.

"I suspect they still need to take another step with harnessing the exhaust blowing effect to increase downforce though. But there's time for that pre-Melbourne."

15:44 Van der Garde shaves a few tenths of his previous best but stays 12th.

15:45 Our first red flag of the day, and with just 15 minutes of the afternoon remaining.

15:46 And it's for the Caterham of van der Garde. Moments after setting his fastest time he's stopped on the outside on the entry to Turn 3.

15:49 The Caterham is now successfully coverd by a green sheet and the lorry is waiting.

15:50 Now the Caterham is swinging its way onto the back of the truck and the marshals and course cars are preparing to leave the scene.

15:52 The truck is setting off the wrong way round the track and back towards the pit entrance.

15:54 Green flag and the session is back underway for a little over six minutes of running.

15:54 Hulkenberg, Bottas, Sutil, Webber, Vergne and Chilton are all straight back out.

15:58 Looks like the order will stand going into the final minute.

15:59 Rosberg is fastest out there and did a new personal best middle sector, but his ultimate time was 1.8s off his best.

15:59 Bottas, Webber and Hulkenberg are lapping in 1m30s, 1m28s and 1m29s respectivey.

16:00 There's the chequered flag, Barcelona day three is done.

16:00 Alonso will head off (Massa is in the car tomorrow) with the fastest time thanks to his morning 1m21.875s.

16:00 Hulkenberg, Grosjean and Rosberg are next up, then the two Williams drivers.

16:01 Returnee Sutil is eighth on the list between Button and Webber.

16:01 Vergne, Chilton and van der Garde - cause of the day's sole red flag - complete the list.

16:03 Final lap count for the day: Alonso 97, Hulkenberg 91, Grosjean 119, Rosberg 107, Maldonado 79, Bottas 67, Button 71, Sutil 78, Webber 108, Vergne 106, Chilton 57, van der Garde 93

16:04 That's all for Thursday's running, keep checking AUTOSPORT for all the news from the paddock tonight, and we'll be back tomorrow morning at 8am GMT for the final day's action.