07:58 5.9 degrees, a gorgeous sunrise and the faint rumble of an F1 engine. It can only be the second day of pre-season testing at Jerez. Welcome back.

08:00 There's been news overnight too, with Luiz Razia announced as Marussia's second driver for 2013. He'll be driving today too, although the team will start late as a result of Max Chilton's crash (for which he wasn't at fault) yesterday. Read the full story here.

08:03 And we're green. Nico Hulkenberg is the first out in what is his second and final day of testing for Sauber at Jerez. The German was enthused by the C32's high-speed handling when AUTOSPORT caught up with him yesterday.

08:05 Four minutes in and we've had Romain Grosjean, Paul di Resta, Pastor Maldonado, Giedo van der Garde, Mark Webber and Felipe Massa all heading out for quick installation laps.

08:06 And now Lewis Hamilton takes to the track in the Mercedes W04, his first competitive outing for his new team.

08:10 Force India on Twitter: "Weights checks done. Install lap complete. No issues to report. @pauldirestaf1 will begin day two in #VJM06 with more aero data collection."

08:12 Razia heads out for his first lap in the Marussia. No hangover for the team from yesterday's shunt then. If you missed the news earlier this morning, the 23-year-old Brazilian was confirmed as the team's second driver for 2013.

08:14 Installation laps done, there's a momentary lull out on track. Sergio Perez and McLaren are the only pairing yet to emerge so far this morning.

08:16 Coming up at 15.00 today we have a Live chat with new Williams driver Valtteri Bottas, and we want your questions. Send them to live@autosport.com, or Tweet us using the hashtag #AUTOSPORTLive. We'll be putting the best questions to him when he drops in.

08:21 Mark Webber sets the day's first competitive time, a 1m24.092s, sailing past the pitlane just as Paul di Resta heads out for Force India. The Scot has the wheel for the morning, before handing over to James Rossiter this afternoon.

08:28 Mark Webber works his way down to a 1m22.611s, which is his penultimate effort of a five-lap run.

08:30 That effort did put Webber top of the timesheets for all of a minute, until Daniel Ricciardo came round. The younger Australian lowers the day's early benchmark to a 1m21.176s, set on his third flyer. He's shod on the orange Pirelli hard compound.

08:32 Our first red flag of the day comes early, although we're not quite sure of the cause as yet.

08:33 Aha. Daniel Ricciardo has stopped out on track between Turns 10 and 11, just before the Ayrton Senna chicane.

08:35 No oil reported on the ground by the Toro Rosso. It's been an efficient marshalling job too - two cars, one low loader and team members have already arrived. The covers are going on as we type.

08:42 Meanwhile in the media centre it's guess the age game, as Edd Straw does his best to deny speculation he turns 50 today. Then again, he's also being sent happy 35th, 40th and 46th messages. Fancy a guess? Tweet him at @eddstrawF1

08:42 The Toro Rosso-bearing low loader is back in the pitlane, and we should be back under way shortly.

08:44 We're green again. As the Toro Rosso is offloaded, Nico Hulkenberg and Giedo van der Garde slide past and out onto the track.

08:48
We have our first sight of Sergio Perez, who heads out in the McLaren MP4-28.

The team enjoyed a mixed day yesterday. Three laps in, it was on the low loader; three laps from the end, suddenly eight tenths clear of the field. Jenson Button admitted he was taken aback by his pace, while his rivals were left scratching their heads. Read it here.

08:51 Van der Garde crawls down the main straight, although there's no hint of a problem as he then rips through Turns 2 and 3.

08:53 Plenty of guesses in the Edd Straw age game, but bizarrely enough the closest is 24. Keep sending them via Twitter, and we'll shout out the first person to guess correctly.

08:54 A whole host of gauges and sensors already today. Williams were running with a rake sensor in front of the sidepods earlier, while Marussia currently have a roll-hoop mounted sensor to gauge airflow.

08:55 It's still only seven degrees here in Jerez, although Formula 1 cars are proving an effective heating tool as the track has crept up eight degrees in just 45 minutes.

08:59 Lewis Hamilton cruises down the main straight in a silver car - still feels a bit strange to see him in anything other than a McLaren.

09:00 Mark Webber has already racked up 11 laps this morning, and he's jumped to the top of the timesheets once again with a 1m20.257s. Daniel Ricciardo is the only man within one second of that right now.

09:01 Marussia on Twitter: "Luiz has 9 laps under his belt as we recommence our familiarisation programme with the #MR02 and start to conduct some testing items"

09:04 Hamilton pits just as Perez heads out.

09:04 And then Perez heads in, meaning we have a brief moment of calm.

09:07 We have a winner in the Edd Straw age game - congratulations to Edo Selimovic. A nice eclectic range of guesses, from 24 to 56. Our money was on 64.

09:11 Nice image of a relaxed Nico Hulkenberg in the cockpit of the C32, courtesy of Sauber.

09:16 Paul di Resta, already with 18 laps under his belt, posts his fastest time of the day with a 1m28.083s.

If you hadn't seen it earlier, he'll be handing over to James Rossiter in the afternoon, before a similar pattern - in opposite order - tomorrow. Di Resta told AUTOSPORT that the arrangement was beneficial for both Rossiter and the team.

"James is very inexperienced in Formula 1 at the moment, but he’s doing our simulator work," he said. "So it’s important for him if he’s going to be working with us this year that he’s in the car and understands the correlation from the simulator."

09:19 Last place in the Edd Straw guessing game goes to AUTOSPORT's Australian correspondent Phil Branagan, who had him pegged in the late 60s. So did we Phil...

09:20 On the track front, Daniel Ricciardo almost joins Mark Webber in the 1m19s. He's now just 0.103s shy of his compatriot, and more than 2.6s clear of Romain Grosjean in third.

09:23 Paul Hembery, Pirelli motorsport director, has been talking about the first official day of running for the company's new compounds. "Early days. But new structure matching expectations so far," he said via Twitter. "We often use Jerez for tyre compound development. Good weather, surface aggressive enough and good layout."

09:24 Lewis Hamilton, on his first proper run in the Mercedes, is now third with a 1m22.062s.

09:30 Luis Razia is the only man out on track right now, Marussia’s new man pounding round in the MR02. He's up to 12 laps, with a best effort some five seconds off Mark Webber - although that's enough to put him fifth fastest for now.

09:31 Only Sergio Perez and Nico Hulkenberg are yet to set a time. The Mexican has just headed out for his fourth lap in the McLaren MP4-28.

09:33 "Most of the aero work is complete," Force India reports on Twitter. "Here's a view of the garage as the guys prep the car for set-up work."

09:34 Perez's first flyer puts him neatly just behind Lewis Hamilton, the man he replaced at McLaren. Half a second to choose between the pair.

09:34 His second is even faster - a 1m21.358s enough to jump him ahead of Hamilton and into third. Romain Grosjean and Luiz Razia, fifth and sixth, also set their own personal bests.

09:39 A lot of green on the timesheets now. First Sergio Perez comes round in a 1m20.709s, moving him to within eight tenths of Webber, and then Grosjean follows suit by jumping to fourth, two tenths of a second down the road. Not to miss out Nico Hulkenberg bangs in a 1m22.223s, his best so far today and enough for sixth.

09:40 All happening. Hulkenberg improves, but moments later the becnhmark he was aiming at is lowered further as Daniel Ricciardo goes fastest.

09:41 Ricciardo's time, incidentally, is the second fastest we've seen so far in Jerez, bettered only by Button yesterday.

09:41 And he's just improved it further, getting down to a 1m19.487s.

09:43 Hamilton exits the pitlane and goes purple in the sector two and three speed traps.

09:44 His first flyer is...well, a flyer too. A 1m19.519s, set on mediums, moves him to second.

09:45 Ricciardo is still out and circulating quickly - a good run this. He's on mediums too.

09:47 Second red of the day, and it's for Lewis Hamilton.

09:48 The Briton is in the gravel at Dry Sack - from the tyre marks, looks like he's locked up and ploughed straight through the gravel.

09:51 Hamilton is out of the car and has walked away from the car. Pretty speedy response as a crane arrives on the scene.

09:52 Our view of the Lewis Hamilton crash.

09:56 The covers are on the car, but the front wing isn't as mechanics wrest it from the scene. The low loader has arrived and the car is being lowered on as we type.

10:00 Update from Mercedes: "Lewis is back in the garage, we're waiting for the car to return to find out what happened"

10:02 The low loader is, the Mercedes mechanics are swarming and the track is green again.

10:04 Giedo van der Garde and Paul di Resta get us underway again. Still a flurry of activity down at Mercedes.

10:07 That's a second straight day of problems for Mercedes, after Nico Rosberg hit trouble early yesterday and had to abandon the rest of the day.

10:14 Jonathan Noble was down at the pitlane as Hamilton's W04 rolled in. Mercedes was tight-lipped, but he did manage to snap this shot of the car on the low loader.

10:16 As he did that, Romain Grosjean was flying - the Frenchman is now the day's fastest driver after clocking a 1m19.080s.

10:19 That incidentally is just over two tenths slower than Jenson Button's day one benchmark - a lap the Frenchman admitted was a handy guide to what Lotus should be aiming at. It's all in AUTOSPORT's Day 1 Blog. We'll even provide a link.

10:27 Nico Hulkenberg and Felipe Massa are the only two men currently out on track. The Ferrari man is on full test mode, coming down the straight at half chat. Unsurprisingly his best is some 20s off the outright pace.

10:29 Hulkenberg jumps into third with a 1m19.502s, which puts him and Sauber within half a second of Romain Grosjean's Lotus E21.

10:31 Personal bests for Paul di Resta and Giedo van der Garde, who sit fifth and eighth respectively.

10:33 Sergio Perez heads out on mediums for McLaren. Di Resta and Grosjean are on the same compound; van der Garde is on hards.

10:37 Improvement for Perez, who comes round in a 1m19.572s and jumps into fifth.

10:41 Jon Noble has the latest on Hamilton's crash - it was caused by a loss of rear brake pressure. Full story coming up on AUTOSPORT.com.

10:48 Paul di Resta continues to rack up mileage in the Force India VJM06 - he's on 41 already, to add to the 89 he managed yesterday.

10:49 Incidentally, teams covered 675 collective laps on the first day of testing yesterday. Last year, it was just 379.

10:51 Williams on Twitter: "Our focus has been aero evaluations so far so it's been a busy morning for our track aero [man] Paul Williams"

10:53 Grosjean, Ricciardo, Hulkenberg - today's fastest three men are all out on track together right now.

10:58 Lewis Hamilton's earlier crash was caused by rear brake problems, the team has confirmed to AUTOSPORT. Read the full story here.



While we're at it, we've been flat out over the last few days bringing you the latest stories from around the world. In case you missed any, here's a quick catch up:

• Jean-Eric Vergne not worried he might lose Toro Rosso drive
• Marussia signs Luiz Razia for second 2013 seat
• Bruno Senna lands Aston Martin GT drive
• Jerez testing blog: McLaren breaks then flies

11:03 As Felipe Massa toils today, Fernando Alonso has been training/relaxing (delete as applicable) on his bike.

"108km - 3:52h. Low intensity," he said on Twitter. "Gym this afternoon."

Massa has managed 14 laps today, none of which have been focussed on outright lap time - evidenced by the 20.617s gap he has to Romain Grosjean at the top of the timesheets.

11:06 Nico Hulkenberg is our only man out on track at the moment. Temperatures have risen to 12 degrees air - which means the jumper can finally come off - and a more balmy 24 degrees on track.

11:11 On his outlap, Webber sets a new best in the sector two speed trap.

11:13 He improves again next time round, both in the speed trap and in his overall time. A 1m19.533s moves him to fifth.

11:14 Felipe Massa, on a more competitive tempo now, puts in two laps in the 1m20s.

11:15 AUTOSPORT is on reserve driver watch - Davide Valsecchi, the team's new third driver, has just wandered down the pitlane.

11:21 Romain Grosjean and Daniel Ricciardo, the day's fastest two drivers, are both out on track, both on mediums and matching each other lap for lap at present. Perez, also on Pirelli's white compound, heads out for McLaren.

11:22 Van der Garde improves to a 1m21.916s.

11:23 In other news, it's difficult to distinguish between the orange hard compound and red super soft. Van der Garde looks to be on the former though.

11:24 Six drivers out on track now, the busiest it's been since the immediate flurry straight after Hamilton's crash.

11:27 A reminder: we want your questions for our live chat with new Williams driver Valtteri Bottas at 1500 today. Get following him on Twitter here, and keep sending questions to live@autosport.com or via Twitter using #AUTOSPORTLive.

11:32 Pit in, pit out - we saw that a lot last year, but Felipe Massa's speedy run through the pitlane might be the first of 2013. One practice start later and the F138 is back on track.

11:33 And again for Massa, although this time he seems to have attracted followers - Mark Webber and Luiz Razia join shortly after the Brazilian's pitlane drive-through.

11:34 Mercedes on Twitter: "Update from Jerez... we have traced the problem to the hydraulic brake line connecting to the right-rear caliper. The impact with the barrier also damaged the front left corner (suspension and associated aero parts). No news yet as to when we will be back out on track."

11:37 On mediums, Mark Webber jumps to third with a 1m19.338s. Once again he's fastest through the sector two speed trap.

11:38 Luiz Razia also goes green, posting a new personal best of 1m23.537s. He stays 10th.

11:40 Romain Grosjean puts the E21 through its paces with a practice start at the end of the pitlane, before heading out for what will be his seventh run of the day.

11:42 Our third red flag of the day, just as Romain Grosjean sets the fastest lap we've seen so far at Jerez.

11:44 The red is for Luiz Razia, who has stopped on the other side of the pit wall. A short walk for the Marussia boys then, and the MR02 is quickly surrounded by red coats.

11:44 Grosjean incidentally came round in a 1m18.828s, some three hundredths of a second faster than Button (1m18.861s) managed yesterday.

11:47 Nice work by Marussia: the WR02 is jacked up onto rollers and pushed the 100m to the nearest break in the pit wall. That will take some beating in the unofficial AUTOSPORT recovery times competition.

11:47 Told you it was quick - we're back to green.

11:51 Grosjean picks up where he left off with a 1m19s on his first flyer.

11:52 That's bettered by Paul di Resta though - the Scot jumps into second overall with a 1m19.094s.

11:56 Grosjean is staying near the pace. Four laps in and he's still lapping regularly in 1m20s.

11:57 Is Lotus going to take morning bragging rights for a second day in a row?

11:57 As we approach Wednesday's halfway point, Grosjean holds a 0.266s advantage over di Resta, with Ricciardo, Webber and Hulkenberg next up.

11:59 Highest mileage belongs to di Resta on 54 laps. Grosjean and Webber are into the mid-40s.

12:00 Lowest tallies belong to Maldonado and Hamilton at seven and 15 apiece.

12:03 Grosjean backs right off for two very slow laps then comes in to end that run. Only action now is van der Garde coming in and out of the pics.

12:05 There's no official lunchbreak at Jerez, but that doesn't mean teams and drivers don't need food. So things will naturally quieten down now for a spell.

12:05 AUTOSPORT journalists live on enthusiasm and style guides rather than food, though, so we'll crack on.

12:06 This is a good chance to think of ever more fascinating questions to put to Valtteri Bottas, our special guest this afternoon. Email your questions to live@autosport.com or use #AUTOSPORT Live on Twitter.

12:07 It's also a good chance to read Edd Straw's trackside verdict on the 2013 F1 machines.

12:12 Di Resta's coming back out now to end that quiet period.

12:16 Ferrari is among the teams stopping for lunch, but here's what it plans to do afterwards: "The afternoon session will continue with an analysis of different exhaust systems."

12:23 Confused about tyre choices for the first test? Pirelli, as ever, is happy to explain:

"We had some questions on the supersoft. Pirelli chose 20 sets of tyres per team (all the same), none of which [were] super-softs. Each team could then chose a further 15 sets, some of which may have been super-softs but that's not for us to comment. All clear now?

"Fastest time yesterday was set by Jenson Button on the new orange hard compound. Jenson's time was 1m18.861s. Fastest time last year on day one was 1m19.670s, set on a medium.

"So the first tendancy shows that this year's hard compound is faster than last year's medium - that's what we wanted to achieve."

12:29 Romain Grosjean and Giedo van der Garde are pounding around during this ad-hoc lunchbreak.

12:33 Five-lap run completed (at an average of 1m21.578s), Grosjean heads back into the Lotus garage.

12:38 And contrary to earlier reports, some AUTOSPORT journalists do need food. A fight over Pistachio nuts is currently breaking out.

12:42 Something we haven't seen for a while - Pastor Maldonado heads out in the 2012-spec FW34. Edd Straw reports that the team picked up a clutch issue on the car on the first run. It was a simple fix, but it took a while for the team to get it in and out of the car.

12:42 Just eight laps for Maldonado so far today.

12:45 Romain Grosjean pulls further clear of the pack with a new best, a 1m18.810s.

12:50 Maldonado has also improved. He gets down to a 1m22.570s, enough to jump ahead of Razia and into 10th.

12:52 The man next up for Maldonado, Caterham's Giedo van der Garde, heads out in the CT03.

12:54 Jon Noble is down at Mercedes, where he reports the team is still trying to work out whether it can run again today or not. Could be a second early close. A decision is expected very soon.

13:00 Nico Hulkenberg heads out for Sauber and looks to be on it from the start, setting a new best in the second sector speed trap.

13:01 Mercedes will sit out the rest of the second day. Jon Noble has confirmed the team needs to halt for repairs to the hydraulics and the rest of the car.

13:02 That's two premature halts in two days for the squad.

13:04 Full story on Mercedes coming up on AUTOSPORT.com.

13:07 And here it is - Mercedes to sit out the rest of the second day.

13:14 Maldonado improves to a 1m21.787s, which puts him ninth. Massa is still some way ahead - 1.8s - but after that, our top 8 is covered by barely more than one second.

13:17 Good battle right now between Paul di Resta and Mark Webber. The Australian hounds the Force India man all the way around the first half of the track, before eventually picking him off on the back section.

13:18 Sergio Perez meanwhile is the fastest man on track at present following his 1m19.937s effort.

13:26 35 minutes until our Live chat with Bottas. And here he is with the magazine that started BOTTAS-mania.

13:27 We've even been tidying up for him. Although for Edd Straw, that means leaving the bin on the desk and then dropping his iPod into it.

13:31 Not much to report on track at the moment. Daniel Ricciardo has been lapping on his own, and Giedo van der Garde has just joined him after a full-on practice start at the end of the pits.

13:33 Van der Garde heads straight back to the pits, and the track falls silent as Ricciardo joins him.

13:35 That was a short run of just four flying laps for Ricciardo, all in the 1m26s. That suggests he was running a heavy fuel load.

13:36 Mark Webber, currently half a second adrift of Romain Grosjean's best time, heads back out. He's joined by new McLaren recruit Sergio Perez.

13:39 In recent years, it's always been fascinating to see how often cars could open the DRS on the lap, particularly in fast corners. There's none of that this year now DRS use will be more restricted on Fridays and Saturdays in 2013. The Red Bull's were always worth a watch on this front, and Mark Webber admitted last night he found himself trying to open it in places where it's not allowed anymore.

13:39 Nico Hulkenberg and Pastor Maldonado have joined Webber and Perez on track.

13:40 Paul di Resta is back out on track. At some point today he is going to hand over to Force India's simulator driver James Rossiter.

13:42 We're briefly up to six of the 11 cars on track now, as Ricciardo heads back out on medium compound tyres. Webber then pits.

13:44 Maldonado improves his time in the 2012 Williams to a 1m21.076. The team is making up for lost time after a clutch problem cost it some running.

13:47 Ahead of James Rossiter's first outing for Force India later today, AUTOSPORT's F1 Editor Edd Straw gives us a rundown of his previous F1 experience: "This is James Rossiter’s first Formula 1 test outing since January 2008, when he drove the Super Aguri AS07B at Jerez. In total, he has 46 days of official testing under his belt having made his debut for BAR at this very circuit in December 2004.

"The majority of his running was in BAR/Honda machinery, with his final outing for that team coming at Barcelona in November 2007. He also completed a total of 12 days for Super Aguri between May 2007 and his final outing. In total, he has completed well over 15,000km in F1 machinery."

13:50 Very similar times being posted by di Resta, Ricciardo and Maldonado at the moment, all in the 1m24-25s bracket.

13:51 As those teams focus on slower runs, van der Garde's Caterham takes the honour of fastest car currently on track with a 1m22.519s

13:52 Valtteri Bottas has arrived...

13:57 Today's current pacesetter Grosjean is back out. At the moment all of the top four are on track, along with van der Garde.

13:58 Naturally, as we say that, one of them pits (Paul di Resta).

14:00 Grosjean wastes no time in lowering today's benchmark even further. He's now down to a 1m18.218s.

14:01 A 1m29.8s from Grosjean that time. Let's see if he winds it up again after that cooling off lap.

14:03 Grosjean is back around, with a 1m19.3s.

14:04 The first answers from Valtteri Bottas will be with us shortly. Here he is warming up for your questions with Sam Tremayne and Edd Straw.

14:06 It turns out BOTTAS is a fan of capital letters. He's just told us we must always write 'MAXIMUM ATTACK' in capitals.

14:06 Our first question of our Live chat with Valtteri Bottas comes from Chris Cassingham:

Did someone from the team prompt you to join Twitter, or did you just think it was time to have an account?

Valtteri Bottas: "The team hinted last year it would be cool if I joined, then they started to tell me some tweets that people had sent saying they would like to see me on it. Finally they've managed to change my mind. I’m not addicted yet, but it’s quite cool."

14:08 Sergio Perez on track at the moment, as is the man he was tipped to replace for 2013, Felipe Massa.

14:10 What are the most useful or important lessons you have learned from Mika Hakkinen?
BB, Hungary

Bottas: "The most important is always MAXIMUM ATTACK."

14:14 Your statistics in previous categories are very impressive for a newcomer into Formula 1. Do you think this will raise expectations for the 2013 season?
Mandeep Dhesi, Manchester

Bottas: "I’ve set the bar quite high for myself: I want to do really well. I believe the team is also expecting quite a lot from me, but it is also a rookie season and I have a lot to learn. At some point of my career I wish to be at the top though, that's the goal."

14:16 It's been a test to forget for Mercedes so far. While the team works on getting its car ready for tomorrow's action, Craig Scarborough adds some insight to the team's F1 W04 here.

14:16 How do you see yourself as a driver. Are you aggressive, smooth, a risk taker?
Taner Selvi, Istanbul

Bottas: "I would describe myself as quite adaptable; I always try to adapt to different scenarios. When it is time to push I will, but if I don’t need to take big risks I will adapt. It will be the same with the tyres this year I think. It's always good to have different approaches."

14:20 Do you think you will gain an advantage by testing the old car, or are you hiding some major improvements that you don’t want other teams to copy?
Petri Teerimaki

Bottas: "It was always the plan to launch the new car in Barcelona, so we can develop the Melbourne package a bit more in the windtunnel. It is still a really valuable test for us even with the old car, because we get to try the 2013 tyres and we also have some new bits on the car. I would expect it to be a reliable car because there are not many technical changes."

14:20 Five cars on track at the moment, and Massa is closing on the Williams of Maldonado. He's been close for a lap or two now, and finally backs off to find space coming out of Turn 2.

14:21 Edd Straw claims he is about to join the AUTOSPORT Live commentary team. Deep breaths all-round...

14:24 Force India is looking good for completing the most laps for the second consecutive day. Paul di Resta is 20 clear of van der Garde in the Caterham.

14:25 Can you explain what kinds of tests are being run at Jerez? How do you know one piece really works if it is connected to an older package that may have been completely re-designed?
Jari Nenonen

Bottas: "We are going to evaluate a lot of different parts, so there are a lot of rigs, sensors and gauges to measure everything. And then of course driver feedback is really important for the team. If you are testing a new part compared to an old one you need to describe the changes in a lot of detail, and the team will then compare that to the data and make a decision on what to go with."

14:27 Van der Garde improves in the Caterham, clocking a 1m21.622s. He stays 10th, half a second adrift of Maldonado.

14:28 With the loss of so many key people at Williams since this time last year, how will the team be able to fight Red Bull, McLaren and Ferrari?
Bill Wedlake

Bottas: "I’m quite confident we can really be a good challenge for the top three teams. We are aiming to have another step forward from last year and I think everything so far is looking good. But it’s still too early to say. I think the first time we will see something is qualifying in Melbourne, but I have a good feeling we can make another step and challenge the top teams."

14:29 Last year during testing, Heikki [Kovalainen] said he'd like to see you racing some day. Do you think he will come back any time soon and would you like him to? Good luck!
Alli Hautamaki

Bottas: "It’s a shame he's not here. Of course three Finns would always be better than two Finns on the track. I would like to see Heikki racing some day again, like he said to me."

14:30 It's not just the teams that are getting preparations in place for the early races of the new season. Talk in the media centre has turned to Chinese visas a couple of times today.

14:33 Updates from the pitlane: Sauber has had no problems with its programme today, while Williams is focusing on tyre work.

14:34 Which F1 driver are you most looking forward to doing battle with?
Barry McManus

Bottas: "I really cannot say one driver, but all the world champions it will be nice to get racing with them. Kimi is Finnish and a world champion so that will definitely be nice. I'm sure the Finns would be really happy to see me having some nice battles with him on TV."

14:37 Grosjean is back on track, and back under the 1m19s barrier. It's 'only' a 1m18.6s this time.

14:38 How different are the simulators to driving the cars in real life?
Adam Gatto

Bottas: "It's tough to compare the simulator with real driving. At Williams we've been improving the simulator all the time. The correlation between both is really close. The general feeling of the car can be especially close, it's just when you drive the real car you get so many more feelings, like the vibration and the g-forces. It's different, but it is a useful tool."

14:45 Grosjean has pitted after that quick run on softs, which was still faster than anyone else has managed today.

14:45 Perez has been told by McLaren he has another 14 laps to go on this run. He is on hard Pirellis.

14:46 Perez is steadily getting quicker on this run so far, down from 1m24.2s to 1m23.5s then 1m23.2s.

14:47 Recent updates to our testing gallery include some technical close-ups, and Martin Whitmarsh in a big coat and slightly rascal-ish scarf.

14:49 Tonight our technical contributor Craig Scarborough will bring full details of new parts seen on the cars today in his tech blog, and check back tomorrow morning for his in-depth analysis of the midfield teams' designs.

14:51 Perez and Maldonado are the only men on track at the moment.

14:52 A bit more action now as Massa and Hulkenberg join in.

14:54 After a few technical glitches, we can bring you the (delayed) final two questions from our Live chat with Valtteri Bottas. First up, it's Jeroen Jonkers.

Which advantage do you think it has that you’ve driven a lot of Fridays last year?

Bottas: "Really, really helpful. If I compare myself to all the other rookies in 2013 I think I have a bit of an edge because I have so much more mileage. Even on the weekends when I wasn't driving I was following closely and trying to learn. Thanks to Williams I think the preparation has, for me, been as good as you can get in modern F1."

14:56 Grosjean is back out, and looking lively with a new best time through the first sector...

14:56 And finally, from Gary Wills:

What are your aims for the season?

Bottas: "To improve as a driver, as quickly and as well as possible. To learn from possible mistakes. To quite quickly manage to keep up with Pastor and put the car where it really belongs. In other words, to get everything out of the car as soon as possible and get to the stage of MAXIMUM ATTACK."

14:57 Grosjean passes Perez as he crosses the line with a 1m18.5s - once again on soft tyres.

14:58 Another afternoon improvement from van der Garde. He's down to a 1m21.311s.

15:00 After a cool-down lap, Grosjean is back on it, but it's only a 1m19.1s. Every time he has tried the hot lap-cool lap-hot lap run this afternoon, the second hot lap has been slower.

15:02 Force India simulator driver James Rossiter has taken to the track for his first taste of the VJM06. So Paul di Resta is done for the day.

15:04 Edd Straw has just been alarmed by some of his fellow F1 journalists singing happy birthday to him across the media centre.

15:09 These tests never pass without little snippets of news breaking. Jonathan Noble reports that the teams are trying to get some extra testing for their 2014 V6 engines

15:10 And we wonder why Fernando Alonso didn't fancy coming to the first test: Felipe Massa passes the pits doing another slow speed aero run.

15:11 Rossiter is back in the pits after his first six laps in the Force India. His best time of 1m23.943s doesn't trouble the overall leaderboard, but there have been plenty of cars going slower than that on heavy fuel runs.

15:15 Grosjean takes to the track, but not for more soft tyre heroics. He's on the hard compound this time, and as he crosses the line with a 1m24.9s he's told there's another 19 laps left on this run.

15:17 Grosjean has lost a couple of tenths per lap in the early stages of this longer run. He briefly has the track to himself, before Hulkenberg and Rossiter join him.

15:21 Force India has sent Rossiter out on the soft tyres. He quickly jumps ahead of Luiz Razia's best time from this morning (before the Marussia hit trouble).

15:23 Rossiter finds another couple of tenths on that lap. He's down to a 1m23.1s, and with time running out today he's unlikely to close the 1.8 seconds required to get ahead of van der Garde's Caterham.

15:24 Talking of van der Garde, he's just returned to the pits after a trip through the gravel (spotted by Jonathan Noble) at the chicane.

15:29 Bizarrely, the first 'tech' row of this test to go public involves one of the cars near the back of the grid. Jonathan Noble explains it here.

15:30 Grosjean's pit board suggests he has eight laps of this run remaining, but the Frenchman is back in the pits and wheeled into the garage.

15:35 @eddstrawf1: "Grosjean looked like he was on a 20-lap run - pit-board was counting him down. Came in with eight to go. Laptimes-wise, presumably he was carrying a lot of fuel. Averaged a 1m25.847secs in the 11 fliers in the run. Started at a 24.955 but dropped well into the 27s by the final two laps. Was on the hard tyres."

15:35 Rossiter proves us wrong by going faster than the Caterham by 0.038s.

15:38 Of note, Rossiter appears to have found all that time despite a switch from the soft to the hard compound tyres.

15:39 Away from the circuit, Jenson Button has found a way to unwind.

"Nice chilled 70km TT bike ride this morning," he says on Twitter, "very different to the craziness at the track!"

15:45 Back at the track, we're into the final 16 minutes of the day. Romain Grosjean's 1m18.218s is still comfortably clear of the rest of the field.

15:47 Felipe Massa and Pastor Maldonado are the only men out on track. Is Williams on the back foot as a result of not having its 2013 car here? Not according to its Venezuelan racewinner - find out why here.

15:48 Romain Grosjean heads out in the Lotus.

15:50 And now Nico Hulkenberg is out for Sauber. We're into the final 10 minutes.

15:52 The Ferrari, Williams, Red Bull and Sauber are all running in each other's wake at the moment. Not a bad way to end the day.

15:56
Webber and Hulkenberg, both on mediums, are the quickest men out on circuit at the moment, but neither really looks like threatening Grosjean's time. There's still four minutes to go, but it looks like being the Frenchman's day.

15:56 And just as we write that, the Frenchman brings the day to a slightly premature close. His E21 is stopped out on track.

15:58 Grosjean is stopped out between Turns 3 and 4, but it turns out he's not alone - Hulkenberg in the Sauber C32 has also stopped out on track.

15:59 Hulkenberg is stopped between Turns 8 and 9. Both drivers are out of their cars.

15:59 So that's a red flag in the final moments, keeping Grosjean - one of the causes of the stoppage - on top.

16:00 Di Resta is second in the Force India, ahead of Ricciardo, Webber and Hulkenberg.

16:00 Keep following AUTOSPORT tonight for news and reaction from the whole paddock, features and our technical analysis.

16:01 Sauber reports that Hulkenberg stopped with a planned shortage of fuel as part of a 'run-dry' test.

16:01 AUTOSPORT Live will return at 9am CET on Thursday for day three of Jerez testing. Thanks for your company today.