Ahead of today's free practice session, the air temperature is 30 degrees C, and the track temperature is 32 degrees. With five minutes to go before the session gets underway, fans, drivers and team personnel are witnessing a most magnificent sunset… with barely a cloud in the sky and not a hint of rain. Humidity is 64%.

McLaren has opted to change the engine in Heikki Kovalainen's car, using the new 'joker' rule, which allows one 'free' engine change a season. According to the team there was nothing seriously wrong with the Finn's engine, merely some extra wear.

Furthermore, following complaints from the drivers, a number of changes have been carried out to the track overnight, including the smoothing out of some of the bumps, particularly at Turns 7 and 8. There have also been much needed changes to the pitlane entrance and exit, following drivers complaints that both were potential black spots.

The lights go green, and behind the Force Indias a whole flurry of drivers are waiting to get to work and check out the modifications. Indeed, all but Barrichello, Hamilton and the Ferraris are on track.

Just three minutes into the session and already Red Bull is suffering. David Coulthard is slowly making his way around the track, telling his crew that he is stuck in third gear. Elsewhere, Bernie Ecclestone is in deep conversation with Jean Todt in the middle of the pitlane.

Five minutes into the session, Hamilton and Barrichello get to work, leaving Massa and Raikkonen as the only 'no shows'.

Glock is the first driver to come out for a second run, the German having spun into the barriers in the final moments of yesterday's second session. The Toyota posts the benchmark, crossing the line at 1:48.097. Elsewhere, Fisichella, Sutil, Trulli and Heidfeld leave the pits.

As Glock improves with a 48.075, Trulli posts 49.657 to go second.

Alonso gets it all wrong at Turn 1 and has to make full use of the generous run off. Meanwhile, Raikkonen is on track on softs (super-softs).

Heidfeld goes second to Glock, with Fisichella third, ahead of Trulli and Sutil.

As Piquet goes quickest (46.910), Raikkonen can only manage 55.372, which is good enough for eleventh. Elsewhere, Massa (softs) leaves the Ferrari garage.

Raikkonen goes quickest (46.482) as his teammate goes quickest in the first sector. The Brazilian crosses the line at 46.830 to go third.

A 46.180 sees Glock re-take the top spot, as Kovalainen watches from the pit-wall, the Finn showing no desire to get to work.

Kubica goes second with a 46.286, but with moments he is demoted as Vettel takes the top spot with a 45.679.

Kubica tells his crew that despite the modifications to the pitlane entry and exit, he finds the entry more "dangerous" than it was before. He advises his team to "inform Charlie", referring to Race Director Charlie Whiting. Thing is, how did the track 'designers' manage to get it so wrong?

Massa goes second with a 46.040, as Hamilton prepares to come out. Thus far, certainly in this session, in these conditions, it's hard to say which compound is the better, the hard (soft) or soft (super-soft).

Just after half-time, and Kovalainen is finally on track, on hards, as is his teammate, who is also on hards. The Finn goes quickest in the second sector, but a minor mistake in sector three means he can only manage sixth (46.484).

With his car bottoming heavily under braking, Robert Kubica's crew opt to adjust the camber on the Pole's BMW.

Button goes eighth and Piquet ninth, the Brazilian improving to first next time around with a 45.249. Hamilton crosses the line at 45.637 to go second, on only his first flying lap.

With twenty-five minutes remaining, it's: Piquet, Hamilton, Vettel, Massa, Glock, Kubica, Raikkonen, Kovalainen, Bourdais and Button. The Red Bulls are at the bottom of the timesheets, with Coulthard the only driver that hasn't posted a time.

On board with Bourdais and it's a scary ride, the Frenchman really fighting the Toro Rosso as he struggles to keep control.

It's not all doom and gloom for Red Bull, form out of nowhere, Webber produces a 45.450 to go second. Elsewhere, after locking-up and heading off down the escape road, Raikkonen makes a pig's ear out of getting back on track. Indeed, despite assistance from the marshals he is unable to rejoin the track having stalled his Ferrari.