Heidfeld fastest in final China practice

Hamilton led much of the hour, but when the field switched to soft tyres in the closing minutes, the McLaren driver was narrowly beaten by Heidfeld, who slipped ahead by 0.074 seconds.

Robert Kubica put the second BMW into third place, just 0.015 seconds behind Hamilton, but Ferrari pair Felipe Massa and Kimi Raikkonen, and recent double race winner Fernando Alonso (Renault) could only manage 12th, 13th and 16th places respectively.

The two Renaults made the early running, before Heikki Kovalainen (McLaren), Hamilton, Massa and then Toro Rosso's Sebastien Bourdais grabbed the top spot in quick succession just after the 20-minute mark.

McLaren then took charge as the session approached its halfway point, with Hamilton only allowing Bourdais one minute at the front before lapping in 1:36.669 to beat the Toro Rosso by 0.191 seconds.

Kovalainen briefly usurped his teammate 12 minutes later, but again Hamilton swiftly returned to the top, out-pacing Kovalainen by 0.155 seconds a few moments later to lead the way going into the late soft tyre runs.

Hamilton's session wasn't entirely trouble-free, though, as he had an uncomfortable reminder of his 2007 retirement at Shanghai when he overshot the tight right-hander in the pit entry at the end of his first run. Unlike last year however, he went down the escape road rather than into the gravel trap, and was able to reverse back on course without drama.

The Briton then extended his advantage further when he switched to soft tyres, lapping in 1:36.135.

Kubica was the first to seriously challenge this time, only to fall fractionally short, but then his teammate Heidfeld did better still and usurped Hamilton in the final minute.

Kovalainen moved back up to fourth on soft tyres, then escaped a near-miss with Giancarlo Fisichella as the Force India emerged from the pit lane.

Jarno Trulli completed the top five for Toyota, ahead of Williams' Nico Rosberg, Bourdais, David Coulthard's Red Bull, Kazuki Nakajima in the second Williams, and Nelson Piquet's Renault.

The Ferraris spent most of the session in the midfield, and only rose to 12th and 13th on soft tyres, while Alonso slipped right back to 18th place and also gained little ground on the softer Bridgestones - although his best time was still only 0.9 seconds off the pace.

All three fared much better than Mark Webber, who could well face an engine change penalty going into qualifying. The Australian's Red Bull stopped on the long back straight in a cloud of smoke after 45 minutes, having apparently suffered a failure in its Renault V8.

Pos  Driver       Car                       Time
 1.  Heidfeld     BMW Sauber           (B)  1:36.061
 2.  Hamilton     McLaren-Mercedes     (B)  1:36.135  + 0.074
 3.  Kubica       BMW Sauber           (B)  1:36.150  + 0.089
 4.  Kovalainen   McLaren-Mercedes     (B)  1:36.324  + 0.263
 5.  Trulli       Toyota               (B)  1:36.396  + 0.335
 6.  Rosberg      Williams-Toyota      (B)  1:36.427  + 0.366
 7.  Bourdais     Toro Rosso-Ferrari   (B)  1:36.642  + 0.581
 8.  Coulthard    Red Bull-Renault     (B)  1:36.712  + 0.651
 9.  Nakajima     Williams-Toyota      (B)  1:36.713  + 0.652
10.  Piquet       Renault              (B)  1:36.789  + 0.728
11.  Barrichello  Honda                (B)  1:36.839  + 0.778
12.  Massa        Ferrari              (B)  1:36.842  + 0.781
13.  Raikkonen    Ferrari              (B)  1:36.901  + 0.840
14.  Vettel       Toro Rosso-Ferrari   (B)  1:36.902  + 0.841
15.  Button       Honda                (B)  1:36.958  + 0.897
16.  Alonso       Renault              (B)  1:36.996  + 0.935
17.  Glock        Toyota               (B)  1:37.053  + 0.992
18.  Webber       Red Bull-Renault     (B)  1:37.566  + 1.505
19.  Sutil        Force India-Ferrari  (B)  1:37.648  + 1.587
20.  Fisichella   Force India-Ferrari  (B)  1:37.964  + 1.903

All timing unofficial