Find out more about our subscriptions
As it happened: Test day three
By Geoff Creighton and Matt Beer
The live commentary has ended. No further updates will be posted.
08:00 Hello and welcome to AUTOSPORT Live for coverage of the penultimate day of pre-season testing for F1 2010 from the Circuit de Catalunya.

08:01 It's a sunny morning at the circuit, despite some local forecasts predicting a chance of rain.

08:02 Installation laps are already getting underway, with teams eager to get the most out of the minimal test time remaining this weekend.

08:04 Nico Rosberg and Felipe Massa are on their first tours of the day at the moment.

08:06 Rosberg clocks the first time of the day with a 1m23.524s in the Mercedes.

08:08 He follows that up with an improvement to 1m22.650s and is the only man circulating for the moment.

08:11 Rosberg pits after setting the early benchmark at a 1m22.181s.

08:14 Although dry, it is quite a chilly morning on the outskirts of Barcelona with air temperature 7.8 Celsius and the track 13.3 degrees.

08:15 Bridgestone's Andy Stobart has some details on the tyre compounds in use here:

@andystobart: "Soft was the main tyre used in Barca on Friday. Track improvement meant better grip, less graining. A soupçon of medium and super soft use"

08:15 The session has been stopped.

08:17 As Rosberg has now arrived back in the pits, it must be Button's McLaren that has come to a halt.

08:18 Button was on his first lap of the day when the McLaren ground to a halt at Turn 11. The recovery truck is on scene now.

08:21 Button in at McLaren is one of the major line-up changes for today, while Massa takes over the Ferrari, Buemi the Toro Rosso, Sutil the Force Inida and Kobayashi the Sauber.

08:22 Rubens Barrichello is also driving the Williams for the rest of the test.

08:24 Button's McLaren is being recovered back to the pits and the action should resume shortly.

08:25 The track is open again.

08:26 Jarno Trulli in the Lotus and Buemi in the Toro Rosso are quickly back on circuit.

08:28 Renault had a troubled Friday, with suspension issues in the afternoon curtailing the team's planned running.

Here's the latest:

@rf1paddockpass: "Slight delay to our day as the team make some changes to the car. We will keep you posted."

08:29 Buemi clocks his first time of the day with a 1m28.325s, while Trulli also gets a lap on the board at 1m28.264s.

08:31 Massa is also out in the Ferrari and sets a 1m26.062s first timed lap of the day.

08:34 Buemi is closing in on Rosberg's early benchmark with a 1m23.570s

08:35 Rosberg is back on track and clocks a 1m21.330s

08:37 Times continue to improve, with Rosberg's best of 1m21.193s now setting the early pace.

08:39 Rosberg, Buemi and Trulli are now back in the pits.

08:41 Barrichello is carrying out set-up work in the Williams, with his times now closing in on the tail end of the leaderboard.

08:42 Sutil has slotted in third quickest on his return to testing the Force India with a 1m24.393s.

08:45 Vitaly Petrov has completed an installation lap in the Renault.

@rf1paddockpass: "Vitaly’s on his install lap now. Checking the radio at all the corners. Coming through loud and clear.."

08:47 Sutil's run continues with his latest effort a 1m22.951s.

08:48 Barrichello is now 12 laps into a run with the Williams and his pace has settled in the 1m26s bracket.

08:49 Buemi is closing in on Rosberg's early benchmark as he sets a 1m21.901s.

08:50 A 1m21.538s on the following tour is some good pace from Buemi's Toro Rosso.

08:52 Ever-improving speed from Buemi, clocking a 1m21.480s then a 1m21.413s.

08:53 Barrichello pits to wrap up a 14-lap first run of the day.

08:54 Sutil and Massa are heading out for some more running.

08:56 Buemi pits at the end of a five-lap stint averaging a 1m21.5s.

08:58 Qualifying will be a major consideration for the teams to work on here as they need to understand how to find a compromise setup that works with low fuel on Saturday afternoons and a full tank to start the race.

Parc ferme, limiting setup changes between qualifying and the race, remains in the rules this year.

08:59 Rosberg, Massa and Sutil are lapping at the moment.

09:00 Massa improves to a 1m23.490s but remains fourth overall for now.

09:01 Meanwhile, Rosberg is back to setting the early pace as he improves the benchmark to a 1m20.891s.

09:02 Rosberg pits after two flying laps and it looks like he is working on qualifying pace this morning.

09:04 Hulkenberg set the best time of the test so far yesterday afternoon at a 1m20.614s, while a 1m19.954s was the best time from Barrichello's Brawn in qualifying last year at the Spanish Grand Prix.

09:05 Sutil is back in the Force India garage, with Massa the only man on circuit at present.

@clubforce passes on some details: "Adrian returns to the pits after another run. 'Lots of graining on the rear tyres. Few set up changes now to address this, and try and get some more rear grip.'"

09:09 Trulli pops up to fifth as he clocks a 1m25.059s for Lotus.

09:11 Teams are casting their eyes to the skies this morning as there is a chance of rain. It has clouded over a little during the first hour.

09:13 Barrichello sets a 1m24.491s in the Williams to take fifth quickest away from Trulli.

Nico Rosberg09:14 Early pacesetter Nico Rosberg is back out in his Mercedes.

09:15 Rosberg improves fractionally with his first flying lap of 1m20.824s.

09:17 A 1m20.686s now for Rosberg, just shy of Hulkenberg's best yesterday.

09:18 Once again it is two flying laps for the Mercedes and Rosberg heads back to the pits.

09:20 Incoming weather is a concern at Lotus Racing:

@MyLotusRacing: "rain coming in so Jarno in pit to look at tyres - car running fine this am but the cold is a bad contrast to yesterday - feels like Norfolk"

09:21 Barrichello is the only man circulating at the moment.

09:23 Mike Gascoyne of Lotus reports: "Slight spots of rain on the circuit now"

09:24 Light rain is definitely moving in, just as Force India send Sutil out for four timed laps.

09:24 They are not happy about that:

@clubforce: "Adrian on the radio now, says it's starting to rain. Dammit."

09:27 Rosberg is undeterred by the passing shower and is out again in his Mercedes.

09:28 Sutil has abandoned his run and is back in the Force India garage.

@clubforce: "Tyres off the car and stacked in the garage while they decide what to do in view of the rain."

09:29 Rosberg completed a slow tour and is now back in the garage, leaving the track silent for now.

09:31 Light rain continues to dampen the Circuit de Catalunya.

09:32 Kobayashi has gone out to test the conditions in his Sauber.

09:33 This is bad news for the teams - especially the McLaren, Red Bull and Virgin outfits that haven't clocked any times so far today.

Richard Branson09:40 Richard Branson is at the circuit to check on the progress of his Virgin Racing squad. Here's some of his thoughts from a breakfast with the media before today's running:

Q & A with Richard Branson

09:41 Meanwhile the rain continues to fall and the only action has been Kobayashi making slow, single laps of the circuit.

09:43 The continuing rain will begin to remove a little of the rubber from the asphalt surface, meaning grip levels will take time to build up again after it dries.

09:44 Jenson Button is now heading out. The McLaren driver hasn't been on circuit since he caused the first red flag of the day in the first hour.

09:47 The world champion makes a visit to the pits but is back on another steady tour.

Light rain continues to fall at the circuit.

09:55 Away from the damp Circuit de Catalunya, Stefan GP continue to push for an entry:

Stefan critical of F1 entry process

09:59 Here's Mike Gascoyne's plans for Louts:

@MikeGascoyne: "Weather not looking good. A race distance is on the test list so we may as well get on with it"

10:00 Kobayashi is out for another look at the conditions in his Sauber.

10:02 Rain continues to fall and is set to significantly disrupt today's running.

10:02 Kobayashi clocks a time - 1m47.093s.

10:03 The rain appears to be getting heavier.

10:05 Virgin Racing has sent out Glock for some running on full wet rubber.

10:06 Kobayashi's latest effort in the wet is a 1m43.264s.

10:08 The continuing rain means teams will have to rethink their plans for today. Toro Rosso tell us they wanted to do some qualifying runs and a race simulation today.

10:10 Kobayashi continues to lap, currently in the 1m42s bracket.

10:13 Trulli has joined the circuit, perhaps to begin the race simulation Mike Gascoyne had planned.

10:16 Confirmed by the man himself:

@MikeGascoyne: "Race distance started. Conditions will be tricky and may be difficult with the tyres and track conditions"

10:17 Weather update from our man @NobleF1:

"The rain is coming down heavier, but the sun has come out too. There must be a rainbow somewhere over Barcelona"

10:18 Jenson Button clocks his first time of the day with a 1m42.234s

10:20 Race simulation also seems to be the plan at Sauber, with Kobayashi now 12 laps in to a run.

10:23 Mercedes plan to send Rosberg out shortly, but he won't be able to challenge those quick laps set earlier in these tricky conditions:

@OfficialMGP: "Signs of some sunshine in Barcelona and Nico's getting ready to go out..."

10:23 The rain has eased a bit in recent minutes and now Barrichello, Trulli, Kobayashi and Button are lapping.

10:25 Kobayashi has just clocked a 2m11.772s, having ran wide at Turn 5 and skipped across the gravel.

10:27 Button is back in the McLaren pit but pacesetter Rosberg is on track as promised.

10:28 The rain continues to ease off, but the track has a lot of drying to do before laps in the 1m20s can resume.

10:29 Kobayashi was 15 laps into his stint before that gravelly moment and has now returned to the Sauber garage to get the car checked over.

10:31 Trulli sets the best time of his run so far with a 1m47.814s on lap eight of his stint.

10:31 Rosberg is the quickest man on track at the moment. His latest tour - 1m42.102s.

10:33 Rosberg finds improving grip as he continues, now setting a 1m39.024s.

10:35 Kobayashi has resumed his race run and is lapping around 1m40s.

10:37 The sun is trying to break through the clouds but some drizzle is still falling.

10:38 Track conditions are best described as damp. There's no standing water, so intermediates are an ideal tyre for now, although they may begin to wear out as the drying continues.

10:39 Currently lapping: Rosberg, Massa, Barrichello, Trulli and Kobayashi.

10:40 The session has been stopped.

10:41 Barrichello seems to have spun into the gravel at Turn 5.

10:43 The Williams is deep in the gravel trap and marshals are heading over to recover it.

10:45 Vettel completed an installation lap just before the red flag. We've seen very little of the Red Bull so far today.

10:46 The stoppage is far from ideal for the teams currently testing a race distance, like Lotus:

@MikeGascoyne: "Red flag has disturbed race distance. Straight out on same tyres when green light"

10:48 Claire Williams on Rubens' spin:

"Our turn to go off, think its a bit slippy out there with the rain"

10:50 Ferrari aren't keen on lapping in these greasy conditions:

@InsideFerrari: "Track condition is very poor with low grip. It does not make too much sense to run now."

10:52 The track is green again, with Buemi, Massa and Glock straight out.

10:53 Trulli is also out again now to continue his race distance.

10:56 Massa clocks a 1m40.481s, while Trulli is in the 1m44s bracket with a hefty fuel load aboard the Lotus.

10:59 Kobayashi and Button are now out too.

10:59 It's the best lap of the day so far for Button - 1m36.667s - having missed the dry running earlier on.

11:02 The Williams team is looking to get Barrichello back out soon:

@ClaireVWilliams:"Boys are checking the car over & clearing the gravel out to get Rubens back out on track ASAP. He's done 37 laps today."

11:03 It's been a quiet morning for Renault, with just six laps so far by Petrov. Here is the plan:

@rf1paddockpass: "Track is drying so we will start set-up work with various fuel levels soon. After that it’s a qualy sim and race distance to end the day."

11:05 Massa has pitted after clocking 1m39s - 1m40s laps on a five-lap run.

11:07 Virgin is sending Glock out on intermediate rubber. Perhaps he will finally set a timed lap.

11:08 Light rain seems to be falling again.

11:09 @MikeGascoyne passes on some feedback from his driver: "Track was drying a bit but Jarno reporting raining more now and times dropping from 1,42s to 1.44s"

11:10 Virgin continue with practice starts and systems checks, but still no time on the board for Glock.

11:15 Dispite the rain, Trulli is now 25 laps into his race simulation.

11:17 Kobayashi is 30 laps into a race distance, interrupted by a gravelly off and a red flag. The Spanish Grand Prix is 66 laps around here.

11:19 Drizzle continues to fall. Kobayashi is setting the best times in the 1m36s bracket.

11:22 Petrov is now six laps into his first proper run of the day and has settled in to a 1m36s pace.

Crowd11:24 An impressive crowd on hand again today. Over 21,000 fans attended yesterday.

11:27 Kobayashi has recently been in for a practice pitstop, continuing his race simulation.

11:32 Ferrari has decided to take an early lunch, given the current track conditions:

@InsideFerrari: "We've anticipated the lunch break in order to have more time to work on the car. It's pointless to run on a track with this condition."

11:36 Trulli has been in the pits for new rubber, having finished off the previous set after 33 laps:

@MikeGascoyne: "Drying track destroyed the inters. Now raining more so quick stop for new inters as no tread left on original set"

11:38 Another rain shower is passing over the circuit, making things wetter again.

11:42 Adrian Sutil has been talking to AUTOSPORT on the upcoming season:

Sutil: New rules will suit my style

11:43 Only race-simulating Trulli and Kobayashi are braving the conditions at the moment.

11:46 Temperatures are chilly with a 11.7 Celsius ambient and 14.4 degrees on track.

11:46 Unfortunately, consistent drizzle remains overhead.

11:48 Trulli is now back in the Lotus pit. Rosberg and Sutil are getting some laps in before the lunch break.

11:48 Rosberg sets a 1m34.665s, which is one of the best times since the rain began.

11:51 Petrov is also out for a few laps in the Renault, clocking times around 1m36s.

11:53 Kobayashi is certainly clocking up the laps with his race run and has now completed 70 so far today.

11:54 @MikeGascoyne explains why Trulli's race run has ended:

"Small off from Jarno. Will clean car and finish last 25 laps of race sim after lunch"

11:56 Kobayashi isn't quite going to make a race distance before lunch, having completed 50 laps since starting the simulation.

11:57 Kobayashi has pitted and apparently taken slicks back out for a brief test of the greasy conditions.

12:00 A 1m37.302s clocked by Kobayashi ahead of the lunch break.

12:00 And now it is lunch at the damp Circuit de Catalunya and time for a one-hour break in the action.

12:01 The cars are trailing back to the pits after a frustrating, rain-affected morning.

12:02 Coverage will continue here from 13:00 GMT.

12:03 In case you missed it, here's a summary of this morning:

Rosberg fastest as rain hits test

12:29 A quick reminder that AUTOSPORT Live coverage continues throughout the season, with minute-by-minute commentary on all the track action at every grand prix.

Live coverage of free practice from Bahrain begins at 06:45 GMT on March 12th.

13:00 The session is about to resume for the final three hours - will the teams get some more dry running?

13:02 Our Spanish correspondent reckons it's unlikely - @eligp: "50 Spanish provinces under alert for winds of up to 160km/h today. Not looking good for those in Barcelona!"

13:02 Here's the Lotus plan from @MikeGascoyne: "Jarno resuming race distance for last 25 laps on dry tyres"

13:04 And here's an update on what Force India had for lunch, @clubforce: "Nice shepherd's pie lunch now ready for afternoon. (That's the team, not Adrian. He had something a bit more 'athletic' of pasta)."

13:05 Button has come back in, leaving Trulli to continue his race simulation. A 1m32.999s lap for the Italian that time, which underlines that conditions are still not great.

13:06 Trulli gets down to 1m30.8s on his next lap, as Button rejoins.

13:12 Button is finding some grip, getting down to 1m24.8s, and then 1m23.9s.

13:12 As he failed to get a time in during the dry running this morning, that's the best time of the day for the world champion.

13:17 Petrov heads out and shaves a second off his earlier best time. Button has pitted, but Barrichello and Buemi are now exploring the conditions.

13:18 Down to 1m24.7s for Petrov next time around, and up to seventh place.

13:19 Trulli is still out but his times have gone up to 1m31s.

@MikeGascoyne: "Jarno reporting rear tyres dropping off"

13:21 Prospects for the afternoon weather look good - with lighter clouds and no rain at present, the track should dry quickly.

13:21 Another improvement from Petrov, but only 0.041s this time.

13:23 Massa sets out to join Buemi, Barrichello, Petrov and Trulli.

13:23 Buemi has been lapping in 1m27s and 1m28s, Barrichello in 1m27s, Petrov in 1m24s and Trulli in 1m31s recently.

13:24 Another personal best from Petrov: 1m24.211s.

13:24 That's it for this run, the Renault pits - while Massa has come straight back in.

13:25 News from @virginracing: "Standard checks over lunch revealed a leaking fuel o-ring which is now being changed."

13:25 Glock has yet to set a flying lap today.

13:28 Sutil sets out. Of those already on track, Trulli is doing 1m30s, Buemi and Barrichello both on 1m28s.

Marc Hynes13:30 Watching the action at Virgin today is the head of its driver development programme - 1999 British Formula 3 champion Marc Hynes.

13:31 Looks like that was a low fuel run from Petrov last time, @rf1paddockpass: "The morning rain means we’ll run a shortened qualy sim this afternoon. And then we’ll get as much of the race distance done as possible."

13:31 Current pacesetter Rosberg leaves the pits.

13:31 Fastest on track at the moment is Sutil - while Barrichello and Buemi have tailed off to 1m29s, the German is on 1m23.3s, not far off his earlier best.

13:33 Expect some long runs and pitstop practice from Rosberg, @officialmgp: "Back out after the lunch break now and Nico will be working on race procedures for the afternoon..."

13:34 Sutil has pitted after three flying laps of 23.7, 23.3 and 23.0.

13:35 Presumably a much heavier fuel load for Williams, as Barrichello completes a seven lap run that averaged in 1m28.7s.

13:37 Massa comes out again.

13:37 Only an out and in lap though. Trulli finishes his run too.

13:38 That was a 23-lap run for Trulli, mostly in 1m30s. Just Robserg and Buemi on track now, doing 1m27s and 1m29s respectively.

13:39 Although Massa and Petrov both set off again.

13:39 As does Button.

13:42 Another improvement from Petrov, down to 1m23.5s.

13:42 Button has come back in, Massa is lapping in 1m27s, as is Rosberg. Buemi continues his long run in 1m29s.

13:44 Petrov gets down to 1m23.0s and jumps to fourth.

Jenson Button13:44 Button rejoins from the pits to continue his run.

13:46 Kobayashi comes out for his first stint of the afternoon.

13:48 Petrov is still doing 1m23s, Massa and Button are on 1m27s, Rosberg and Buemi on 1m28s and 1m29s.

13:51 Petrov pits, that was a six lap run, all between 1m23.0s and 1m23.6s.

13:56 Fastest man in action now is Sutil, who is lapping in 1m24s. Buemi and Button are doing 1m27s, Kobayashi 1m28s and Massa and Rosberg 1m29s.

13:59 Several drivers head for the pits. Sutil had done 4 laps, mostly in low 1m24s, and Kobayashi did six laps between 1m27.1s and 1m29.6s.

14:00 News from Force India on that last run, from @clubforce: "Adrian's back in after a performance run. Seems quite happy, says the car feels 'consistent.' It's raining again though now."

14:05 It's started raining again at Barcelona. Buemi, Massa and Button continue with their runs nevertheless.

14:05 Times haven't gone up too much yet, Massa did 1m26s last time.

14:05 Vettel completes his first flying lap of the day, a 1m26.2s.

14:06 Eight tenths quicker on the next lap, which puts him ahead of Kobayashi.

14:06 Everyone has now set a time today apart from Glock.

14:08 Vettel gets down to 1m24.892s, and up to eighth position.

14:09 @virginracing promises we'll see Glock soon: "All going back together now, so hopefully not too long..."

14:10 @clubforce: "Oh dear. test boredom nigh. One of guys walking around with a cup stuck on his headphones. He doesn't know he has a cup stuck to his head."

14:11 If it wasn't for Twitter, we would never have discovered how F1 teams keep themselves amused on rainy test days.

14:11 The track is getting busier again now though, with Sutil heading out as well as Rosberg. Buemi, Massa, Button and Vettel are still on track.

14:12 Vettel dropped back to a 1m25.1s, and then came within 0.002s of his best from earlier in the run.

Fans14:15 The fans on the right are clearly getting excited about Kubica resuming running tomorrow. It's less clear who those on the left are cheering for...

14:16 Massa and Button are 22 and 20 laps into long runs respectively, with the Ferrari doing 1m26s and the McLaren on 1m28s.

14:17 Everyone is currently out except Barrichello, Trulli, Kobayashi and Glock.

14:18 Vettel pits, having done an eight-lap run, mostly in high 1m24s and low 1m25s, although one 1m30s lap happened in the middle.

14:19 Petrov jumps to third place with a 1m22.833s.

14:19 That's the best time we've seen in a few hours.

14:21 Now down to 1m22.671s for Petrov.

14:21 Renault has confirmed that this is a qualifying simulation for Petrov, and he pits after that second quick lap.

14:23 A very long run for Buemi, now on his 41st lap on doing 1m26.7s.

14:23 Massa and Button are both in low to mid 1m26s as their long stints continue.

14:26 Quick update on the lap count, the top mileage so far today is from Kobayashi on 89 laps, then Rosberg on 88, Trulli on 85 and Buemi on 82.

14:26 Vettel has done just 13, Glock hasn't done a flying lap.

14:31 Vettel takes half a second off his previous best, and Petrov sets out again and improves by a tenth too.

Vitaly Petrov14:31 Another 22.5 from Petrov on his second flying lap.

14:32 Only Trulli and Glock in the pits now, all the established teams are on track.

14:34 That was just a two lap sprint for Petrov again and he's back in the pits.

14:35 Kobayashi pits after an eight lap run, mostly in 1m28s, with two mid-1m27s laps in the middle.

14:35 A slight - 0.06s - improvement from Vettel again.

14:36 Sutil improves by 0.2s, and stays fourth.

14:37 The long runs continue: Button up to 33 laps this time, Massa on 35 and Buemi on 50

14:38 Buemi and Massa are in mid-1m26s, Button in mid-1m25s.

14:41 Sutil has just done a four lap run: 23.1, 22.7, 23.9 and 22.8.

14:47 As they press on with their long stints, Button has been consistently about half a second faster than Massa recently - producing high 1m25s to the Ferrari's mid-1m26s

14:48 Rosberg has become the first man to go over 100 laps today, hitting 104 for Mercedes now.

14:52 Button pits for a tyre change then starts lapping in mid-1m24s.

14:52 Massa is back in low 1m26s, but has done 37 laps on this set of tyres.

14:55 @virginracing should manage some miles at last in the final hour: Just "firing up, then a few more minutes and we should be good to go"

Sebastien Buemi14:56 Buemi finishes his marathon stint. The Toro Rosso did 63 laps, pitting briefly after 21, and averaged 1m27.6s.

14:59 Massa just made a quick pit visit then resumed his long run, which is now on lap 52.

15:01 Vettel improves to 1m24.175s but stays eighth.

15:01 Into the last hour, it's still Rosberg on top by 0.7s over Buemi and 1.8s over Petrov.

15:01 Great pace from Massa on his new tyres - a personal best of 1m22.716s.

15:02 That compares to the high 1m24s that Button set on his first few laps out of the pits. The McLaren is now doing high 1m23s.

15:02 Quicker still for Massa - he does a 1m22.479s and goes third.

15:03 Further back, Vettel improves his time by 0.025s.

15:03 And by another 0.009s on his next lap.

15:04 After just under 90 minutes in the Lotus pit, Trulli has rejoined.

15:04 Vettel keeps chipping away, another tenth quicker now and down to 1m24.028s.

15:07 Rosberg is on a race simulation too. He's 34 laps in, pitted for tyres four laps ago, and is lapping in mid-1m22s.

15:07 Vettel gets into the 1m23s and edges ahead of Barrichello into seventh.

15:09 Massa's times since that last pitstop: 22.7, 22.4, 22.9, 22.7, 22.8, 22.7

Felipe Massa15:09 And now a 1m22.344s, his quickest of the day.

15:10 Here comes Glock at last after that repair to a fuel leak, @virginracing: "And off we go. That was a long job but necessary for safety."

15:13 Finally Glock gets a time on the board: 1m31.976s.

15:15 Seven tenths quicker on Glock's second lap.

15:16 Vettel has finished a 10 lap run, mostly in 1m24s but with a few odd laps 5-10s slower.

15:18 Glock gets down to 1m30.8s.

15:18 The session has been stopped.

15:18 Rosberg stops on track and brings out the reds.

15:19 The current pacesetter was 41 laps into this long run and doing mid-1m23s.

Michael Schumacher15:25 When he finished testing yesterday, Michael Schumacher was pessimistic about Mercedes' prospects. But he's more optimistic today after examining the data

Schumacher revises Mercedes prediction

15:25 The session has restarted.

15:26 Just over half an hour remaining as the green light comes on. Buemi is first out.

15:26 Petrov and Trulli quick to rejoin too.

15:27 @insideferrari is happy: "Another race simulation successfully completed for the F10."

15:30 The session has been stopped.

15:30 Just minutes after the green, out comes the red again.

15:31 It's Buemi who caused this one. The Toro Rosso came into a halt in the final corners.

15:35 Renault's plan courtesy of @rf1paddockpass: "Another red flag has stopped Vitaly’s long run. When it goes green he’ll be running till the end."

15:40 While we wait for the session to resume, here are Michael Schumacher's thoughts in full.

15:41 The session has restarted.

Nico Rosberg15:42 The action gets back underway, 18 minutes to go - will conditions be good enough for anyone to get near Rosberg?

15:42 Petrov, Sutil, Trulli and Kobayashi set off first.

15:43 Massa, Button and Vettel come out too.

15:46 Barrichello joins in, so it's just Rosberg, Buemi and Glock in the pits.

15:46 The stoppages are going to make it hard to judge who's doing what in these final laps - with no way of telling whether those on long runs are picking up where they left off or starting afresh on new tyres and different fuel.

15:46 Kobayashi back in, Glock leaves the pits.

15:47 Button goes up to third with a 1m22.127s, while Vettel does a personal best of 1m23.254s.

15:48 Massa, Sutil and Trulli all come back in after single laps.

15:49 Mercedes news from @officialmgp: "Small technical gremlin stopped Nico out on track. All fixed and he's heading back out again very soon..."

15:49 Only Petrov, Barrichello, Vettel and Glock still out.

15:49 And Barrichello grabs third with Button with a 1m22.0s.

15:50 A massive improvement from Glock too - 3.6s quicker than earlier, although he is still slowest.

15:50 Another 0.9s faster for the Virgin next time around, Glock is edging closer to Kobayashi's 10th place.

Rubens Barrichello15:51 Barrichello goes a further tenth quicker.

15:52 Rosberg's glitch is fixed and he leaves the Mercedes pit.

15:53 A very busy track now, only Buemi - who recently had a problem - is in the pits. Seven minutes to go.

15:55 Button goes half a second quicker than before and reclaims third from Barrichello on 1m21.6s.

15:56 A 0.1s improvement from Sutil, who stays seventh.

15:56 Rosberg sets the best sector one time of the day, but is half a second shy of his morning pace around the full lap.

15:56 Button improves again, down to 1m21.450s but still third.

15:57 The session has been stopped.

15:57 Just as things are hotting up, out comes the red flag.

15:57 With only three minutes on the clock, that's probably the end of today's action.

15:58 It's Barrichello who stopped this time.

15:59 The chequered flag comes out as expected.

16:00 So that's the end of the penultimate day of winter testing for 2010.

16:00 Rosberg's pre-rain time of 1m20.686s stands as the best of the session, ahead of Buemi, Button, Barrichello and Massa.

16:01 Rosberg also has the highest mileage today, completing 128 laps. Massa was next up on 115, Buemi did 106, Button and Kobayashi 105, and Trulli 102.

16:01 But just 31 for Glock.

16:01 Thanks for following events from Barcelona with AUTOSPORT. We'll be back for another day of live testing coverage from 8am UK time tomorrow.

P Driver Team Time
1  RosbergMercedes 1m20.686s
2  BuemiToro Rosso 1m21.413s  +0.727
3  ButtonMcLaren 1m21.450s  +0.764
4  BarrichelloWilliams 1m21.975s  +1.289
5  MassaFerrari 1m22.344s  +1.658
6  PetrovRenault 1m22.523s  +1.837
7  SutilForce India 1m22.606s  +1.920
8  VettelRed Bull 1m23.254s  +2.568
9  TrulliLotus 1m25.059s  +4.373
10  KobayashiSauber 1m26.216s  +5.530
11  GlockVirgin 1m26.305s  +5.619
All timing unofficial. Updated: 15:56 GMT
Overcast High Temp: 14°C / 57°F
Track: Dry
Loading info ...