Rubens Barrichello put the Brawn team on top in the first free practice session for the European Grand Prix at Valencia.
As Brawn seeks to recover some competitive ground to its championship rival Red Bull, the Brazilian set his 1m42.460s lap with 15 minutes of the session still to go. He then looked like he was going to improve on the final moments before his car became stuck in gear.
Under-pressure Heikki Kovalainen went second fastest, using a new McLaren front wing to do so, 0.018sec ahead of his teammate Lewis Hamilton.
Jenson Button was fastest for a long period in the session but dropped to fourth, 0.6sec slower than his teammate.
Sebastian Vettel was the top Red Bull driver in fifth position, having swapped positions with Button at the front earlier on.
Adrian Sutil was an impressive sixth quickest for the improving Force India team, another team to have brought a package of updates to Valencia.
Kazuki Nakajima was seventh for Williams ahead of Mark Webber's Red Bull. Fernando Alonso and Kimi Raikkonen meanwhile completed the top 10.
There were no serious incidents in the 90 minutes, though several drivers went the wrong side of the kerbs on the dirty asphalt surface. Indeed, the fact that the field was split by more than 3sec suggested that the track conditions improved rapidly through the session.
Jaime Alguersuari was the fastest of the three rookies in 13th position for Toro Rosso (he also shared the most laps with teammate Sebastien Buemi).
Renault's Romain Grosjean was 17th -- just over a second slower than Fernando Alonso. The Frenchman was one of the first drivers out, much like F1 returnee Luca Badoer.
The Italian Ferrari driver was slowest of the runners, 3.380sec off the pace of Barrichello and more than two seconds behind teammate Raikkonen.
Pos Driver Team Time Laps
1. Barrichello Brawn GP-Mercedes (B) 1:42.460 19
2. Kovalainen McLaren-Mercedes (B) 1:42.636 +0.176 16
3. Hamilton McLaren-Mercedes (B) 1:42.654 +0.194 18
4. Button Brawn GP-Mercedes (B) 1:43.074 +0.614 19
5. Vettel Red Bull-Renault (B) 1:43.088 +0.628 17
6. Sutil Force India-Mercedes (B) 1:43.209 +0.749 13
7. Nakajima Williams-Toyota (B) 1:43.225 +0.765 25
8. Webber Red Bull-Renault (B) 1:43.243 +0.783 19
9. Alonso Renault (B) 1:43.345 +0.885 18
10. Raikkonen Ferrari (B) 1:43.384 +0.924 23
11. Buemi Toro Rosso-Ferrari (B) 1:43.389 +0.929 30
12. Kubica BMW Sauber (B) 1:43.419 +0.959 20
13. Alguersuari Toro Rosso-Ferrari (B) 1:43.637 +1.177 30
14. Rosberg Williams-Toyota (B) 1:43.746 +1.286 22
15. Heidfeld BMW Sauber (B) 1:44.040 +1.580 23
16. Fisichella Force India-Mercedes (B) 1:44.126 +1.666 17
17. Grosjean Renault (B) 1:44.356 +1.896 23
18. Trulli Toyota (B) 1:44.638 +2.178 26
19. Glock Toyota (B) 1:44.732 +2.272 28
20. Badoer Ferrari (B) 1:45.840 +3.380 25
All timing unofficial