Vettel edges Alonso in final practice for the Canadian Grand Prix

Just 0.006 seconds split Vettel's Red Bull and Alonso's Ferrari, with Lewis Hamilton taking third for McLaren, and Mark Webber (Red Bull) and Pastor Maldonado (Williams) completing the top five.

The session had seen plenty of activity at the top of the timesheets even before the late switches to super soft tyres. Jenson Button's McLaren emerged ahead once the early runs had been completed, but he was soon usurped by Vettel, who set benchmarks of first 1m15.440s then 1m15.022s to sit in first place at the mid-way point.

Alonso beat him soon afterwards, clocking a 1m14.737s despite locking up into the final chicane, although the Ferrari's time in front was very short-lived as Hamilton went 0.025s quicker mere seconds later.

Continuing the close action, when Vettel reclaimed the top spot with 16 minutes to go, his 1m14.711s was just 0.001s faster than the McLaren.

As more and more drivers moved onto super softs, Alonso was the first to really exploit their potential with a 1m14.448s nine minutes from the chequered flag.

That held up until Vettel came through a scant 0.006s faster six minutes later. The German turned traffic into an advantage as he grabbed a tow from Michael Schumacher's Mercedes. Vettel then went quicker still in the first two sectors on his final lap before lost time in the final part of the lap, although his existing 1m14.442s was sufficient to secure first position.

Two drivers will go into qualifying with no Saturday running at all. Nico Rosberg's Mercedes cut out and parked on track on a very early installation lap, while Toro Rosso's Jean-Eric Vergne ended up parked in the Turn 2 tyres after making a mess of Turn 1 on his first flying lap.

There may be issues for Kimi Raikkonen as well, with the Lotus driver under investigation for making a last-minute swerve into the pitlane after a mistake at the final chicane.

Just 1.056s covered the top 16 cars, as the Montreal times remained typically close. Behind the leaders, Felipe Massa maintained his encouraging form for Ferrari in sixth, followed by Schumacher, Lotus duo Romain Grosjean and Raikkonen, and Force India's Nico Hulkenberg. Jenson Button was only 15th for McLaren and expressed concern about brake balance issues over the radio.

Pos  Driver                Team                  Time              Laps
 1.  Sebastian Vettel      Red Bull-Renault      1m14.442            22
 2.  Fernando Alonso       Ferrari               1m14.448s  + 0.006  17
 3.  Lewis Hamilton        McLaren-Mercedes      1m14.712s  + 0.270  19
 4.  Mark Webber           Red Bull-Renault      1m14.724s  + 0.282  21
 5.  Pastor Maldonado      Williams-Renault      1m14.755s  + 0.313  22
 6.  Felipe Massa          Ferrari               1m14.767s  + 0.325  21
 7.  Michael Schumacher    Mercedes              1m14.796s  + 0.354  19
 8.  Romain Grosjean       Lotus-Renault         1m14.873s  + 0.431  20
 9.  Kimi Raikkonen        Lotus-Renault         1m14.977s  + 0.535  21
10.  Nico Hulkenberg       Force India-Mercedes  1m14.992s  + 0.550  22
11.  Paul di Resta         Force India-Mercedes  1m15.067s  + 0.625  19
12.  Sergio Perez          Sauber-Ferrari        1m15.112s  + 0.670  21
13.  Kamui Kobayashi       Sauber-Ferrari        1m15.126s  + 0.684  24
14.  Bruno Senna           Williams-Renault      1m15.237s  + 0.795  22
15.  Jenson Button         McLaren-Mercedes      1m15.327s  + 0.885  22
16.  Daniel Ricciardo      Toro Rosso-Ferrari    1m15.498s  + 1.056  19
17.  Vitaly Petrov         Caterham-Renault      1m16.268s  + 1.826  24
18.  Heikki Kovalainen     Caterham-Renault      1m16.545s  + 2.103  20
19.  Pedro de la Rosa      HRT-Cosworth          1m17.705s  + 3.263  21
20.  Timo Glock            Marussia-Cosworth     1m17.974s  + 3.532  23
21.  Narain Karthikeyan    HRT-Cosworth          1m18.189s  + 3.747  21
22.  Charles Pic           Marussia-Cosworth     1m18.684s  + 4.242  23
23.  Jean-Eric Vergne      Toro Rosso-Ferrari    no time             3 
24.  Nico Rosberg          Mercedes              no time             1 

All Timing Unofficial