How the race will unfold -update

The fuel weights have been released showing that Sebastien Vettel was 17 kilos lighter than the Brawn of Rubens Barrichello in qualifying this afternoon, this is worth about 6 laps.

Based on these figures I reckon that Vettel will stop around lap 12 or 13, the classic first stint for a three stopper, and he could well be looking at running the soft tyres in that short first stint to get them out of the way. The Red Bull is not able to match the way the Brawn looks after the soft tyre on a long run and this looks like Red Bull strategy guru Neil Martin giving his guys the best way to challenge for the win.

Barrichello looks a shade stronger than Button given that he is ahead despite carrying a little more fuel (2kg). These two will fight Vettel and Webber for the win and I think the Brawns will come out on top. But they don't want to lose too much ground in the first stint and they are going to have to deal with Webber, who may play a role for his team mate.

What was interesting was the margin between Vettel and Button was the same in the low fuel Q2 as it was with fuel in Q3 and yet the fuel Button had in Q3 was slowing him down by 4/10ths! So he must have either been sandbagging a bit, carrying more than the minimum of fuel. And yet after the session he himself highlighted the relative Q2 performances.

I think this can be partly explained by the Brawn still not being at its best on low fuel single lap running, whereas the Red Bull, a typical Adrian Newey car, is. The Brawn is happier when it has some fuel in it. Rubens was only 3/10ths slower than Vettel but the extra fuel he was carrying slowed him by 6/10ths, so the Brawn is still 3/10ths faster.

Also impressive was the Toyota of Jarno Trulli, who was seven tenths off Vettel, the exact amount his extra fuel is worth. He will need to make up places at the start if he isto use his strategy to challenge for the win.

Alonso is very light but with the field spreading out in the first ten laps, he'll be hoping that when he pits early, he can take on a lot of fuel for the middle stint on hard tyres and convert his grid slot into a meaningful result.

The Ferrari of Raikkonen and the McLaren of Hamilton both went heavy, some 30kgs more than Vettel, which is 11 laps worth. Fuel adjusted they are not terribly fast, Raikkonen is 2 secs off Vettel and the extra fuel is worth only 1.05secs.

1. Vettel 644.0kg

2. Alonso 637.0kg

3. Webber 646.5kg

4. Barichello 661.0kg

5. Button 659.0kg

6. Trulli 664.5kg

7. Rosberg 650.5kg

8. Raikkonen 673.5kg

9. Hamilton 679.0kg

10. Buemi 673.0kg

11. Heidfeld 679.0kg

12. Kovalainen 697.0kg

13. Massa 690.0kg

14. Glock 652.0kg

15. Nakajima 682.7kg

16. Bourdais 690.0kg

17. Piquet 697.9kg

18. Kubica 659.0kg

19. Sutil 648.0kg