Ahead of today's sole practice session, the air temperature is 21 degrees C, while the track temperature is 32 degrees. The sky is blue but it's quite windy.

Hamilton topped the timesheets in both sessions yesterday however, Alonso and Button gave him a run for his money, with Webber, Vettel and Massa in hot pursuit.

The warmer conditions today will play into Ferrari's hands. However, with the Virgins and HRTs posting times outside the 107% limit yesterday it will be interesting to see how they fare this afternoon... especially if the big guns use the option rubber.

Tyres this weekend are soft (prime) and supersoft (option) the softer rubber around 1s quicker but only good for one hot lap. Indeed, the primes were good yesterday with little degradation and some respectable times being posted even at the end of long runs. The supersofts are good for around 15 laps… suggesting a three stop strategy with softs used for two stints. Again, McLaren and Ferrari appeared to have the edge.

To add to Vettel's misery, his crew worked through the night stripping his car right down after he complained that he wasn't happy with it. Some sections of the media - admittedly as hysterical as its British cousins - claim the youngster's title bid is blown.

The lights go green and Kovalainen leads the way, followed by Glock, Liuzzi, d'Ambrosio, Trulli and Ricciardo. Indeed, within a minute or two everyone has been out for an exploratory lap.

Both Red Bulls are running the same front wing today, Vettel unhappy with the version he used in Germany. Also, there are a few minor differences to the diffuser. Both Williams drivers running different front wings.

Eight minutes into the session, d'Ambrosio is the first driver out for a second run. The Belgian crosses the line at 1:32.884 as Kovalainen, Glock, Liuzzi, Trulli, Kobayashi and Perez head down the pitlane.

No sooner has d'Ambrosio improved to 30.634 than Kobayashi posts a 27.338. Moments later, the Japanese posts a 26.188 while teammate Perez goes second with a 26.246.

More and more drivers pour on to the track, the Mercedes duo going quickest, Rosberg posting a 24.464. However, the Silver cars were highly disappointing yesterday and we're not expecting much of them this weekend.

A 23.526 sees Button go quickest, the Englishman the first of the front runners to make an appearance - apologies to Rosberg and Schumacher.

Schumacher complains that after just 6 laps he is losing the rear tyres. The German is on the soft compound.

As Alonso consolidates his top spot with a 23.016, Vettel begins his first flying lap and Alonso claims into his Ferrari.

Having gone quickest in the last two sectors, Vettel goes quickest overall, crossing the line at 22.360. Hamilton goes second with a 22.978 and Webber fourth (23.629). Next time around the Australian improves with a 23.207 but remains fourth.

Hamilton runs wide as Vettel goes quickest in S1 and again in S2. Webber posts 22.857 to go second. Vettel crosses the line at 22.021, giving him a comfort cushion of 0.836s.

Hamilton is told that having found two-tenth on his last lap he still needs to find another two-tenths.

As Maldonado runs wide, there is frenzied activity in the Mercedes garage where the crews are working on both Schumacher's and Rosberg's cars.

Approaching half time, the Ferrari duo finally leave the pits. On his first flying lap Massa goes fifth (23.722) and Alonso sixteenth (25.572). The Spaniard, in particular, appears to be on a heavy fuel load.

As Trulli gets all out of shape in Turn 9, Schumacher is back on track on options - the first driver to make thee switch. At the second split he is already 0.85s down on Vettel even though the German is pushing hard. Then again, he could be on a heavy fuel load. Elsewhere, Massa run wide in 6/7 and is lucky not to clout the barriers.

Rosberg (options) goes quickest in S1 and posts a PB in S2. The German crosses the line at 22.534, thereby going second.

Replay shows something fly off Liuzzi's car - possibly a front wing endplate. The Italian is currently twenty-third, 6.9s off the pace.