Alonso goes quickest in final practice

The Ferrari driver was the first to engage in a low fuel 'qualifying run' and set a 1m54.099s lap time.

But Nico Rosberg proved that qualifying will be a thriller by almost eclipsing the double world champion moments later, the Mercedes driver setting faster first and second sector times, only to lose out in the third. The German ended the session second, 0.269s back.

Mark Webber moved up to third for Red Bull ahead of Michael Schumacher, who was still trailing his team-mate Rosberg by a couple of tenths.

Sebastian Vettel was fifth fastest ahead of Felipe Massa whose final attempt was squandered as he ran wide in Turn 22. The lap was still good enough for sixth.

Jenson Button was seventh for McLaren, while Robert Kubica, Vitantonio Liuzzi and Nico Hulkenberg completed the top ten.

Red Bull's drivers were the first to get serious in the session as the team tried to make up for the time it perceived to have lost on Friday, and Sebastian Vettel was quickly to down a 1m55.178s - the fastest lap of the weekend so far.

He was joined by team-mate Webber, and then, within the next five minutes most of the rest of the frontrunners.

An interesting five minutes saw the top positions switch around a number of times as first Ferrari's Fernando Alonso, then team-mate Felipe Massa lowered Vettel's mark. The Brazilian, returning to competition following his head injury sustained in Hungary last year, set a 1m54.761s.

Behind him Rosberg all but matched it to go 0.084s and split the Ferraris.

While all this was going on there was drama for Virgin as Timo Glock turned into a tight left-hander, then watched in horror as his left-front wheel departed the car and rolled off on its own trajectory. The problem was apparently identified to an issue with an under-torqued airgun.

Others struggling during the morning were Glock's team-mate Lucas di Grassi, who had a gearbox problem, and Karun Chandhok, whose HRT Dallara failed to find any gear - rendering the Indian wihout any practice experience ahead of qualifying.

Perhaps more significantly for the outcome of the weekend however, Lewis Hamilton was forced to miss out on his qualifying simulation run at the end of the session after a problem with his McLaren's front left brake duct.

Pos  Driver         Team                     Time               Laps
 1.  Alonso         Ferrari                  1:54.099            14
 2.  Rosberg        Mercedes                 1:54.368  + 0.269   13
 3.  Webber         Red Bull-Renault         1:54.500  + 0.401   15
 4.  Schumacher     Mercedes                 1:54.533  + 0.434   13
 5.  Vettel         Red Bull-Renault         1:54.646  + 0.547   16
 6.  Massa          Ferrari                  1:54.739  + 0.640   14
 7.  Button         McLaren-Mercedes         1:55.000  + 0.901   14
 8.  Kubica         Renault                  1:55.331  + 1.232   15
 9.  Liuzzi         Force India-Mercedes     1:55.432  + 1.333   11
10.  Hulkenberg     Williams-Cosworth        1:55.461  + 1.362   13
11.  Sutil          Force India-Mercedes     1:55.521  + 1.422   13
12.  Hamilton       McLaren-Mercedes         1:55.860  + 1.761    8
13.  de la Rosa     Sauber-Ferrari           1:56.063  + 1.964   14
14.  Barrichello    Williams-Cosworth        1:56.259  + 2.160   15
15.  Buemi          Toro Rosso-Ferrari       1:56.295  + 2.196   17
16.  Alguersuari    Toro Rosso-Ferrari       1:56.504  + 2.405   16
17.  Kobayashi      Sauber-Ferrari           1:56.530  + 2.431   13
18.  Petrov         Renault                  1:56.811  + 2.712   16
19.  Glock          Virgin-Cosworth          1:59.173  + 5.074   10
20.  Kovalainen     Lotus-Cosworth           1:59.789  + 5.690   15
21.  Trulli         Lotus-Cosworth           2:01.259  + 7.160    5
22.  Senna          HRT-Cosworth             2:04.001  + 9.902   11
23.  di Grassi      Virgin-Cosworth                               2
24.  Chandhok       HRT-Cosworth

All Timing Unofficial