Ferrari's Felipe Massa was second, having been fastest until teams switched to soft tyre runs and qualifying simulations in the closing minutes.

As has been their habit in final practice so far in 2008, Ferrari and McLaren appeared to focus on heavier fuel loads in preparation for Q3.

Massa was the only member of the usual top four near the front, as teammate Kimi Raikkonen ended the session in ninth, with McLaren's Heikki Kovalainen and Lewis Hamilton in 10th and 18th respectively.

Ferrari sat out the first 37 minutes of the session - preferring to let their rivals clean away the dirt built up by the support races.

When Massa did emerge, he immediately showed his potential by leaping straight to the top of the timing screens with a 1:33.219 lap, beating early pace-setter Rosberg by 0.202 seconds.

Teammate Raikkonen made errors on both his first two flying laps, including a trip across the Turn 13 run-off area on his second lap. When he finally produced a clean lap at the third attempt, he was half a second slower than Massa.

After Hamilton damaged his McLaren's tub in his heavy practice accident on Friday afternoon, the team built up their spare chassis to use for the rest of the weekend.

Apart from a period when Hamilton held second place behind Rosberg, McLaren did not feature amongst the front-runners in the session.

Massa remained on top until the final minutes, when the wholesale switch to soft tyres saw a flurry of changes in the top ten. BMW's Robert Kubica was briefly fastest, but was pushed right back to seventh as others improved in the last minute.

Rosberg was first to usurp Kubica, lapping in 1:32.521. This was 0.205 seconds faster than Massa's final effort, with Mark Webber producing a similar late improvement to take third for Red Bull.

Toyota's Jarno Trulli, Webber's teammate David Coulthard and Williams driver Kazuki Nakajima completed the top six ahead of Kubica and Renault's Nelson Piquet.

The level of activity in the closing stages was such that the Hondas fell to 14th and 16th, having been third and fourth with three minutes remaining.

Times were also extremely close, with just 1.03 seconds covering the top 14 cars.