Ahead of this afternoon's session, the air temperature is 27 degrees C and the track temperature is 40 degrees. It remains bright and sunny.

Michael Schumacher led the way this morning with teammate Nico Rosberg third, the Mercedes duo looking very strong here. Separating the Silver Arrows was Spa winner Jenson Button, the Englishman eager to build on last weekend's revival.

While Fernando Alonso was fourth, ahead of teammate Felipe Massa, his morning was somewhat marred by an engine failure at the end of the session.

Lewis Hamilton, the centre of much media speculation this weekend, was sixth quickest, ahead of Raikkonen, Perez, Webber and Maldonado who suffered a hydraulics problem that brought his session to an early end.

Almost everyone was caught out by the kerbs at one stage or another, Kimi Raikkonen, in particular, suffering a couple of bruising encounters.

In the Mercedes garage, even after 300 Grands Prix, Schumacher is agitated when he's caught out and an engine fires up without having put his earplugs in.

Tyre options this weekend are hard and medium, though we didn't see the softer rubber this morning.

Perez and Raikkonen lead the way when the lights go green, followed by Karthikeyan, d'Ambrosio, Kobayashi and Senna. Alonso watches from the comfort of the Ferrari garage as his mechanics change his engine.

Another 'observer' is Romain Grosjean who is serving a one race ban, the Swiss sitting on the pitwall as he watches d'Ambrosio drive his car.

Within moments of the start of the session Raikkonen has posted a 26.093, ahead of Maldonado, Perez, di Resta, Vergne and Petrov.

Perez and Petrov both make mistakes at the first chicane, the Mexican almost tripping up over a Marussia in his eagerness to get into the corner first.

As Vettel goes second (26.647), Hulkenberg goes quickest in S1, the German ultimately crossing the line at 26.611 to go fourth.

A 26.398 sees Button go second ahead of Perez, Hulkenberg, di Resta and Vettel.

Just eight minutes into the session there are twenty-one names on the timesheets.

Raikkonen consolidates his top spot with a 25.934 as Button closes in with a 26.164. Following this morning's close encounters with the kerbs Lotus has had to make repairs to the Finn's front wing and floor.

Hamilton goes second with a 26.048 and Rosberg third (26.061) as Alonso and de la Rosa remain the only drivers yet to post a time,

Massa posts 26.104 to go fourth but Rosberg and Button are both set to improve. Elsewhere, Schumacher goes sixth with a 26.259.

Having gone quickest in S1, Button crosses the line at 25.832 to go quickest however, moments later, Rosberg ups the ante with a 25.446. Schumacher is informed that he has a DRS failure. Worryingly, the German is also informed that there is nothing the team can do about it during the session.

A 25.611 sees Massa improve to second, teammate Alonso going third (25.713) moments later.

Next time around Massa posts 25.545 while his Spanish teammate posts 25.564 - very evenly matched. That said, Alonso subsequently improves with a 25.350, thereby selling a few thousand more general admission tickets for Saturday and Sunday.

Twenty-five minutes into the session, Kovalainen is the first driver to switch to the medium rubber. Moments later, teammate Petrov takes to the track, the Russian also using the softer rubber.

His first flying lap on the medium sees Kovalainen fail to improve his time. Teammate Petrov also fails to improve but does post a PB in S2.

As Rosberg learns that he has a DRS problem, the cameras pick up Tonio Liuzzi in the HRT garage.

On his fourth lap on the softer rubber Kovalainen finally improves going from 27.487 to 26.935.