Red Bull still looks on course to dominate the Spanish Grand Prix after another one-two in final practice at Catalunya. Sebastian Vettel led the way with a 0.704-second margin over teammate Mark Webber.
The Australian had usurped McLaren's Lewis Hamilton as the pacesetter halfway through the hour, but while Vettel made big gains on soft tires at the end, Webber's earlier benchmark remained his best time. He improved in individual sectors, but did not manage to put a full lap together.
McLaren ended up third and fourth with Hamilton and Jenson Button, as Michael Schumacher continued his promising form by taking fifth for Mercedes.
The Ferraris of Felipe Massa and Fernando Alonso were back in sixth and eighth, sandwiching Mercedes' Nico Rosberg.
Adrian Sutil hung on to 10th place behind Robert Kubica (Renault), despite coming to a halt at the side of the track with five minutes left when his Force India suddenly lost power.
There was one red-flag stoppage 20 minutes in, when both Sauber's Kamui Kobayashi and Renault's Vitaly Petrov had separate incidents in quick succession at Turn 4. While the Sauber spun harmlessly into the gravel, the Renault snapped violently left as it braked and clattered down the tire wall, damaging both ends.
The marshals' efforts to clear water from the kerbing at the corner during the subsequent eight-minute yellow hinted at why both drivers might have been caught out.
Lotus had a 1-2 in the unofficial class for new teams, with Jarno Trulli fractionally ahead of Heikki Kovalainen, and both just over 4sec off the outright pace. Hispania's Bruno Senna was solidly last having been stranded in the garage with a leak on his car for much of the hour.
Pos Driver Team Time Laps
1. Vettel Red Bull-Renault 1:20.528 15
2. Webber Red Bull-Renault 1:21.232 + 0.704 11
3. Hamilton McLaren-Mercedes 1:21.348 + 0.820 14
4. Button McLaren-Mercedes 1:21.376 + 0.848 16
5. Schumacher Mercedes 1:21.583 + 1.055 14
6. Massa Ferrari 1:21.749 + 1.221 16
7. Rosberg Mercedes 1:22.013 + 1.485 14
8. Alonso Ferrari 1:22.091 + 1.563 15
9. Kubica Renault 1:22.242 + 1.714 20
10. Sutil Force India-Mercedes 1:22.377 + 1.849 12
11. Buemi Toro Rosso-Ferrari 1:22.400 + 1.872 18
12. Kobayashi Sauber-Ferrari 1:22.412 + 1.884 11
13. de la Rosa Sauber-Ferrari 1:22.527 + 1.999 20
14. Hulkenberg Williams-Cosworth 1:22.634 + 2.106 16
15. Alguersuari Toro Rosso-Ferrari 1:22.926 + 2.398 20
16. Barrichello Williams-Cosworth 1:22.953 + 2.425 16
17. Liuzzi Force India-Mercedes 1:23.597 + 3.069 12
18. Petrov Renault 1:23.896 + 3.368 5
19. Trulli Lotus-Cosworth 1:24.610 + 4.082 14
20. Kovalainen Lotus-Cosworth 1:24.745 + 4.217 11
21. Glock Virgin-Cosworth 1:25.722 + 5.194 15
22. di Grassi Virgin-Cosworth 1:25.855 + 5.327 14
23. Chandhok HRT-Cosworth 1:26.611 + 6.083 18
24. Senna HRT-Cosworth 1:30.246 + 9.718 6
All Timing Unofficial