Ahead of today's second free practice session, the air temperature is 28 degrees C, while the track temperature is 38 degrees.

We understand that Narain Karthikeyan had an engine problem in the first session, which is why he didn't post a time. He has now changed his engine. We're not sure of the precise problem but we understand that it is 'similar' to that which affected Monteiro in Hungary.

Meanwhile, talking of the Portuguese driver… Monteiro is suffering badly from toothache. He initially refused to have it looked at by team principal Colin Kolles who is a dentist, but having been under the cosh of a local female dentist, reverted to Kolles after all - and was impressed.

However, he isn't cured and hasn't slept at all well. Fortunately, it's not painful in the car, but "it's the worst weekend of my life..." he says.

Nonetheless, Tiago is first out, followed by Trulli, Klien, Ralf, Michael and Raikkonen.

Meanwhile the Ferrari crew is working frantically on Barrichello's car, both drivers having been well off the pace in the first session.

Klien is first to post a time (28.835), as Ralf goes second ahead of Monteiro, Doornbos and Raikkonen.

As Ralf goes quickest (28.281), brother Michael goes second ahead of Villeneuve.

However, it isn't long before it's 'business as usual', as Raikkonen goes quickest (26.978).

Ferrari is still clearly struggling with its set-up, Michael goes off, but so does Trulli.

It's McLaren 1-2 as Montoya goes quickest with a 1:26.748. Behind the McLarens, the Renaults are 3-4, with Alonso being the quicker of the blue and yellow duo.

Heidfeld goes sixth, but the guy getting all the attention is Klien, who goes fifth with a 1:27.919.

The Austrian is leapfrogged by Webber (27.597), as Button splits the Renaults with a 1:27.335. Moments later his teammate (Sato) goes sixth with a 1:27.586.

Button improves again, to go third behind the McLarens, and then takes second with a 1:26.922.

Webber goes off, the Australian appearing to have trouble with his right-rear tyre (loss of pressure?). He goes off, but rejoins the track and slowly makes his way back to the pits. Elsewhere, Massa goes fifteenth (28.842).

If it wasn't red, you'd think that Rubens Barrichello was driving a Minardi, his Ferrari looks truly terrible, a real beast to drive.

With twenty minutes remaining it goes a little quiet… until Fisichella goes quickest in the final sector. Elsewhere, teammate Alonso improves (27.317) but remains sixth.

Raikkonen goes quickest in the first sector, but loses ground in the second after getting a little too exuberant and missing his braking point and leaving the track. Albers also has a 'moment', the Minardi clearly suffering from oversteer.

As Montoya sets a personal best in the second sector, Button goes quickest in the first. The Englishman finally crosses the line at 1:26.599, to go quickest.

With ten minutes remaining there are just four cars on track - Webber, Coulthard, Massa and Michael.

The German improves (28.155), but remains fourteenth, over 1.55s off the pace. This is looking very bad for the Maranello team, which is clearly struggling.

Webber improves (27.335) but remains seventh.

Narain Karthikeyan is still in the Jordan pit having failed to post a time in either session.

Raikkonen sets a personal best in the first sector, then goes quickest in the second. The Finn crosses the line at 1:26.286 to go quickest. Elsewhere, Trulli leapfrogs Heidfeld to take twelfth.

Alonso posts 1:26.627 to go third, as Raikkonen consolidates his top spot with a 1:26.120.

It looks as though new tyres hardly have any effect on this tarmac, several drivers have been out on new tyres and very few have bettered their previous personal best.

Villeneuve improves (28.534) to take fifteenth and thereby split the Ferraris. Elsewhere, Heidfeld, who is on a quick lap, spins just before the chicane. He is able to continue but has run out of time.