Lewis Hamilton put McLaren back on top in the final practice session in Montreal, though all four top teams had a car in the leading four positions, and the top seven places were filled by six different squads.
The McLarens were quickest for the majority of the session, with Hamilton generally holding the top spot and regularly improving his benchmark times until he got down to a best of 1m16.259s on the harder tires. Even on the super-soft tires, no one was able to beat that time, and Hamilton then went faster still on his softer rubber, improving to 1m16.058s, before lightly brushing the wall on his next lap. Just afterward, the yellow flags came out when Lucas di Grassi spun off at the hairpin, preventing anyone else from putting a flat-out lap in during the last minute.
Mark Webber took second for Red Bull, 0.282sec behind Hamilton and just ahead of Ferrari's Fernando Alonso. Michael Schumacher (Mercedes) was fourth, with Sebastian Vettel fifth as Red Bull was the only team to get both cars in the top five.
Renault's Robert Kubica and Force India's Adrian Sutil were next up, while after battling Hamilton for the top spot for a while, Jenson Button eventually dropped to eighth in the second McLaren. Tonio Liuzzi and Vitaly Petrov completed the top 10for Force India and Renault respectively.
Felipe Massa was only 12th, and concerned that he might have damaged his Ferrari when he scraped the wall late on.
Mercedes' Nico Rosberg had to sit out most of the hour with clutch issues, only getting out for a very brief run at the end, leaving him 18th. He was still better off than Karun Chandhok, whose Hispania stopped in the pit exit with hydraulic problems as he tried to set out when the session commenced.
Pos Driver Team Time Laps
1. Hamilton McLaren-Mercedes 1:16.058 15
2. Webber Red Bull-Renault 1:16.340 + 0.282 16
3. Alonso Ferrari 1:16.495 + 0.437 19
4. Schumacher Mercedes 1:16.536 + 0.478 15
5. Vettel Red Bull-Renault 1:16.582 + 0.524 16
6. Kubica Renault 1:16.653 + 0.595 18
7. Sutil Force India-Mercedes 1:16.673 + 0.615 15
8. Button McLaren-Mercedes 1:16.699 + 0.641 16
9. Liuzzi Force India-Mercedes 1:16.814 + 0.756 15
10. Petrov Renault 1:16.982 + 0.924 18
11. Hulkenberg Williams-Cosworth 1:17.121 + 1.063 16
12. Massa Ferrari 1:17.231 + 1.173 16
13. Alguersuari Toro Rosso-Ferrari 1:17.331 + 1.273 22
14. Kobayashi Sauber-Ferrari 1:17.548 + 1.490 20
15. de la Rosa Sauber-Ferrari 1:17.609 + 1.551 16
16. Buemi Toro Rosso-Ferrari 1:17.633 + 1.575 21
17. Barrichello Williams-Cosworth 1:17.789 + 1.731 18
18. Rosberg Mercedes 1:17.979 + 1.921 4
19. Trulli Lotus-Cosworth 1:19.013 + 2.955 15
20. Kovalainen Lotus-Cosworth 1:19.447 + 3.389 16
21. Glock Virgin-Cosworth 1:19.536 + 3.478 22
22. di Grassi Virgin-Cosworth 1:19.844 + 3.786 20
23. Senna HRT-Cosworth 1:20.325 + 4.267 18
24. Chandhok HRT-Cosworth 1