Ahead of today's second practice session, the air temperature is 25 degrees C, while the track temperature is 36 degrees.

While BMW appeared to have made a significant step forward earlier today, the same cannot be said of McLaren, or, to a lesser extent, Ferrari. Nonetheless, the opening session is rarely a great yardstick so we should get a better idea this afternoon.

Due to a problem with the fuel cell on his car, Adrian Sutil will play no part in this afternoon's activities.

The lights go green and Vettel leads the way, followed by Trulli, Rosberg and Piquet.

No sooner has Vettel posted the first time of the afternoon (1:26.109), than Toro Rosso's Sebastien Buemi, still on his out lap, stops on track smoke and flames pouring from the rear brakes. His car is pushed to the side of the track, his session over before it had really begun.

Five minutes into the session, there are 10 names on the sheets, with Kubica leading the way (25.197), ahead of Piquet, Webber and Nakajima.

As Hamilton begins his first flying lap, Piquet goes quickest with a 24.198. There is talk that the Brazilian has until next month's British GP to improve or face being dropped.

The times continue to tumble with Kubica and Glock demoting Piquet as Barrichello goes fourth. Next time around the Brawn driver goes quickest, crossing the line at 23.348.

Vettel goes second (23.469) as Hamilton improves to fifth. Raikkonen and Massa are currently twelfth and thirteenth.

Button improves to third, making it a Brawn 1-3, subsequently going on to take the top spot with a 23.057, as the Brackley outfit suggests it could be 'business as usual' this weekend, despite all the talk of fears that the former Honda team is losing ground to its rivals.

Piquet re-takes the top spot with a 22.740, as Nakajima improves to eighth having gone quickest in the final sector. Next time around the Japanese driver goes quickest with a 22.551.

As Vettel goes quickest in the first two sectors, teammate Webber goes second overall. The German finally crosses the line at 22.400 to go quickest.

Replays show Hamilton's McLaren bouncing like a kangaroo while Massa gets all out of shape but manages to keep it under control.

Nakajima goes quickest in the first two sectors, crossing the line at 21.805 to re-take the top spot.

Heidfeld takes a vicious looking across the kerbing, the F1.09 taking a real pounding. Nonetheless, car and driver are able to continue.

Coming up to half-time, Kovalainen, looking totally committed, posts personal bests in the first two sectors, finally crossing the line at 23.478 to go eleventh.

Nakajima is quickest, ahead of Vettel, Barrichello, Webber, Piquet, Rosberg, Button, Glock, Hamilton and Raikkonen.

Piquet goes off at Turn 9 and is stuck in the gravel. However, courtesy of the ever-obliging marshals, the Brazilian is able to continue. Nonetheless, sitting on the pit-wall Flavio Briatore looks far from impressed.

With thirty-five minutes remaining, Trulli has completed 32 laps, with Glock and Rosberg both on 31.

Massa (softs) is pushing hard, but is only able to move up from thirteenth to tenth.

Rosberg improves to third as Williams looks set to continue its Friday practice form.

Having gone fourth, Alonso goes quickest in the second sector of his next lap, however, a weak final sector sees the local favourite fail to improve. Meanwhile, Rosberg posts a 21.731 to go quickest and thereby make it a Williams 1-2.

Following his earlier brake problem, Buemi is back on track. The Swiss drives goes fourteenth with a 23.036.

Another off and another 'get out of jail free card' for Piquet, as he spins off and appears stuck in the gravel, only to get the Renault moving again.