Ahead of today's sole practice session the air temperature is 26 degrees C, while the track temperature is 29 degrees. It remains bright and sunny.

While Lewis Hamilton posted the fastest overall time yesterday, it was Sebastian Vettel who had the pace in (what appeared to be) qualifying form. Indeed, when running as they will in the early stages of Sunday's race the Red Bulls appeared to have a distinct edge. That said, the Milton Keynes outfit worked late into the night on Mark Webber's car.

Michael Schumacher pleased his many fans here by posting the third fastest time of the day, but teammate Nico Rosberg's KERS problems was proof that Mercedes shouldn't get its hopes up.

Sadly, at least for the partisan crowd, the Ferraris are struggling, and the Italian team will have to produce one of its Monza Specials if is to start from the front tomorrow far less repeat last year's result.

Of real interest was the pace of the Saubers while Renault is looking strong.

The big news this morning, and one that is likely to cause unease long after the 'circus' leaves Monza is that the FIA has ruled that Pirelli's suggested camber limit is mandatory. This follows what happened in Spa when Red Bull exceeded the recommended limit and then blamed the Italian manufacturer citing safety concerns. Other than causing a bitter row between the two, the result is that Pirelli has gone to the FIA, (rightly) voiced its concerns but results in the teams having a vital part of their set-up compromised.

Also, overnight, the FIA has altered the kerbs and speed bumps at the second chicane (Roggia) after a number of incidents when drivers, having got it wrong at the chicane, were forced over what they felt were extremely harsh and unforgiving speed bumps.

The lights go green and d'Ambrosio leads the way, followed by Liuzzi, di Resta, Kobayashi, Ricciardo, Kovalainen and Glock. Both Mercedes drivers are eager to get to work.

Exactly five minutes into the session, Vettel heads down the pitlane, the German enjoying the luxury of having the track to himself.

Despite having only done an installation lap, Ferrari is making changes to the front wing on Alonso's car. As Vettel returns to the pits, the McLarens take to the track.

As Luca di Montezemolo arrives in the Ferrari garage Massa heads down the pitlane, as do Kovalainen and d'Ambrosio.

D'Ambrosio posts the first time of the day, the Belgian crossing the line at 1:32.578. Moments later Kovalainen posts a 29.327 and teammate Trulli a 29.663.

Rosberg goes third with a 29.453 only to be leapfrogged when teammate Schumacher goes quickest with a 26.943. The seven-time champ has been running consistently wide this weekend, particularly at the second Lesmo and the exit to Ascari. Next time around Schumacher improves with a 26.153.

No sooner has Schumacher consolidated his position that Rosberg takes the top spot with a 24.957 while Button goes second and Webber third. Cameras catch Schumacher getting it wrong and spinning at the first chicane.

As Rosberg improves to 24.688, Webber goes second and Hamilton third (25.258).

Twenty minutes into the session all but Massa, Alonso and Vettel have posted times.

A 24.489 sees Button go quickest, McLaren continuing to run noticeably more rear wing than its rivals.

On his first flying lap Vettel goes fourth (24.816) while Hamilton is told he has to find time in the second and third sectors. Meanwhile, Webber goes quickest with a 24.468, the Australian, contrary to some reports, not having changed the engine in his car.

Petrov - sporting a black helmet in tribute to the victims of the Russian air crash earlier this week - goes seventh with a 25.853. Elsewhere, Vettel, having gone quickest in S2, maintains his pace in S3, crossing the line at 24.000 to go quickest. Once again, we have a Red Bull 1-2.

Both Ferraris on track, both drivers sporting considerably more downforce at the front. Meanwhile, the cameras catch (Mercedes Motorsport boss) Norbert Haug taking pictures at the first chicane.

On his first flying lap Alonso posts 26.027 - 2.027s off the pace - while Massa posts 25.850. Next time around, Alonso improves to 25.767 while his teammate doesn't.