World champion Vettel the only man not to set a time as his RB7 was too damaged in the first session.
Free Practice 2
Follow the Turkish Grand Prix live with Eurosport. The race starts at 13:00 on 6 May 2011. Find race results, standings, stats, scores and track info. Keep up with the top F1 drivers and teams including Lewis Hamilton (Mercedes), Valteri Bottas (Mercedes) and Max Verstappen (Red Bull Racing).
Formula 1 fans can read breaking Formula 1 news, interviews, expert commentary and watch free replays. Don’t miss the upcoming Formula 1 events. Make Eurosport your go-to source for sports online from Formula 1 to football, tennis, snooker and more. Enjoy live streaming of this season’s top sports competitions.
Button is followed by Rosberg, Hamilton, Schumi, Webber, Massa, Petrov and Di Resta - the Brit doing well to snatch eighth.
The chequered flag is out... and Button tops the final times after the laps are completed.
Rubens Barrichello has a water leak in his KERS and will not set another lap-time.
Jerome d'Ambrosio's Virgin holding up the multiple champion. He is 21st ahead of HRT's Vitantonio Liuzzi.
Schumacher has been in and come back out again, keen to wring all the data he can from the Merc.
The yellow flags are put away - five minutes to get some quick laps in. Button still leads the times.
Williams rookie Maldonado told Planet F1 prior to the weekend: "Turn eight is spectacular. It's very fast and there are a few bumps, so you have to be very accurate with your line. There are a lot of g-forces, so it's a tough corner for the neck as well. I've been working hard on my fitness since the last race." It didn't help him there.
Yellow flags are out - and Schumacher also spins after seeming surprised at the sudden appearance of a Force India inside him. He misses the barriers though in his Mercedes Silver Arrow.
Maldonado touches the astroturf at turn eight and loses it... he flies sideways and the front wing catches the tyre barrier.
The top 10: 1.Button 2.Rosberg 3.Hamilton 4.Schumacher 5.Webber 6.Massa 7.Petrov 8.Di Resta 9.Perez 10.Sutil
Hamilton out on softs. There are fears the Pirelli tyres will not last around here in warmer conditions - check out our F2 expert Will Gray's blog on the subject.
Vettel not likely to take part in this session, which could cost him - only one hour-long session to come after this one.
Webber runs wide at turn six on to the artificial grass. He corrects the line to rejoin the track.
Rosberg is in the pits, as is Button. Alonso jumps to 11th.
Although the Turkish GP is a relatively new addition to the calendar, turn eight has already found an entry into F1 folklore as one of the best corners of the season.
Rosberg looking good for P1 but loses out in the final sector. 1:26.521 keeps him second.
Nick Heidfeld is currently 11th.
Button shoots to the top of the timesheets with 1:26.456 on the option tyre. Hamilton yet to reappear.
Schumacher third with 1:27.063 in the latest of his short runs designed to improve his qualifying performance.
Sergio Perez, like Hamilton on soft tyres, jumps to fourth in the Sauber.
Webber has pitted while Rosberg improves again to 1:26.961.
Marshals return the Ferrari F150 to the pitlane.
Alonso spins the Ferrari before turn seven but is able to keep it running and drive on.
Webber second but is two-tenths off the leader's pace.
Webber emerges after a lengthy stay in the pits while Rosberg improves to a blistering 1:26.961.
Schumacher second with 1:27.892. Rosberg takes P1 back with 1:27.352 on soft tyres.
Pastor Maldonado spins the Williams's wheels as he slides sideways at turn eight. He eventually gets it under control.
Massa sorts out whatever it was that was hindering him in the second half of the lap to go P1 with 1:27.959.
Hamilton and Button are back in.
Something similar happens on his next lap - but he improves to sixth.
Massa quick in the first sector but remains 11th.
Rosberg, still second, not running at present. The McLaren boys are third and fourth.
Hamilton returns to the fray - the car suffers on the bumpy turn 12.
Schumi's timed effort was the only one of that run-out - he is back in the pits.
Schumacher jumps from 22nd to top spot in one go. His time is 1:28.165.
Eddie Jordan on the BBC says one of the dangers of Istanbul is setting your car up mainly for turn eight. The G-force experienced by drivers at 168mph through the four-apex corner is 4.48 - and it puts incredible stresses on right side tyres.
The track is almost completely dry now with only a few cars out there at present.
Rosberg goes top with 1:28.215.
The McLarens are back in the garage, still P1 and 2.
Webber has made 22 passes this season, but not led Vettel at any point. The percentage of laps led by Vettel this year is 74.7. Surprisingly Rosberg is next up on 8.2 per cent while Button and Hamilton are third and fourth on 7.6 and 5.3 per cent respectively.
Button now leads from Hamilton, 1:28.222 the benchmark.
Vettel's Red Bull is still being worked on in the garage - his front wing was wrecked.
Ferrari's Fernando Alonso went fastest in a wet first practice while Sebastian Vettel crashed into the barriers at the notorious turn eight.
Hamilton has improved to 1:28.345, two-tenths quicker than his team-mate. Neither set a time in the first session.
The top 10: 1.Hamilton 2.Button 3.Massa 4.Alonso 5.Petrov 6.Barrichello 7.Rosberg 8.Heidfeld 9.Alguersuari 10.Di Resta
Rosberg comes back in after a five-lap stint.
Hamilton with 1:29.030 to better the leading time of Vitaly Petrov - 1:29.926.
The moveable rear wings will be allowed in this 90-minute session, unlike in the wet this morning.
Several drivers have already set a time. Hamilton now top with 1:30.970.
Buemi with the first lap-time of 1:33.022.
Narain Karthikeyan and Nico Rosberg follow. There are damp areas but slick tyres can be used already.
Jaime Alguersuari and Sebastien Buemi are first out on to the circuit.
Formula One's leading drivers will be keen to make use of a drying track after a wet opening session in Istanbul.
Welcome to coverage of second practice for the Turkish Grand Prix.