Piquet fastest in final practice

Under pressure to improve his qualifying performances after the difficult start to his Formula One career, the Brazilian rookie led the way for the majority of the session.

Piquet's hard tyre laptime was sufficient to keep him at the head of the pack as few drivers gained time when they switched to softs in the final minutes.

Mark Webber took second for Red Bull Racing, with Sebastian Vettel maintaining his superb practice form by taking third place in his Toro Rosso.

As usual, the likely front-runners ran heavier fuel loads in this session in preparation for Q3. Kimi Raikkonen (Ferrari) was the best of the likely pole contenders in fifth place, behind Williams' Nico Rosberg.

A variety of drivers had swapped the top spot in the first half of the session, including both Toro Rosso drivers, before Piquet stamped his authority on the hour.

He usurped Vettel with a 1:16.344 lap on the harder tyres after 22 minutes, and although he was beaten by Lewis Hamilton soon afterwards, Piquet's second run was quick enough to move him back ahead - his 1:15.750 lap beating the McLaren by four tenths of a second.

Webber was the first major contender to try soft tyres, and closed to within 0.009 seconds of Piquet, who then failed to improve his time when he tried softs shortly afterwards - despite setting a new benchmark in the middle sector.

Vettel had remained in the top ten all morning, and shot back up to third when he switched to the softer Bridgestones, with Rosberg also making a late jump up the order to secure fourth.

Behind sixth-placed Jarno Trulli's Toyota, Hamilton ended up seventh after an error at the Imola chicane on his soft tyre run.

Sebastien Bourdais (Toro Rosso), Felipe Massa (Ferrari) and David Coulthard (Red Bull) completed the top tens.

Likely Q3 contenders Fernando Alonso, Heikki Kovalainen and BMW duo Robert Kubica and Nick Heidfeld appeared to be focusing on heavier fuel runs, as they ended the morning in 12th, 13th, 14th and 18th places respectively.

Pos  Driver        Team                     Time              Laps
 1.  Piquet        Renault             (B)  1:15.750           19
 2.  Webber        Red Bull-Renault    (B)  1:15.759 + 0.009   14
 3.  Vettel        Toro Rosso-Ferrari  (B)  1:15.827 + 0.077   21
 4.  Rosberg       Williams-Toyota     (B)  1:15.974 + 0.224   17
 5.  Raikkonen     Ferrari             (B)  1:16.003 + 0.253   18
 6.  Trulli        Toyota              (B)  1:16.147 + 0.397   20
 7.  Hamilton      McLaren-Mercedes    (B)  1:16.182 + 0.432   16
 8.  Bourdais      Toro Rosso-Ferrari  (B)  1:16.235 + 0.485   18
 9.  Massa         Ferrari             (B)  1:16.256 + 0.506   17
10.  Coulthard     Red Bull-Renault    (B)  1:16.282 + 0.532   18
11.  Glock         Toyota              (B)  1:16.344 + 0.594   20
12.  Alonso        Renault             (B)  1:16.437 + 0.687   20
13.  Kovalainen    McLaren-Mercedes    (B)  1:16.545 + 0.795   16
14.  Kubica        BMW Sauber          (B)  1:16.617 + 0.867   20
15.  Nakajima      Williams-Toyota     (B)  1:16.644 + 0.894   16
16.  Button        Honda               (B)  1:16.651 + 0.901   20
17.  Barrichello   Honda               (B)  1:16.658 + 0.908   17
18.  Heidfeld      BMW Sauber          (B)  1:16.687 + 0.937   19
19.  Fisichella    Force India-Ferrari (B)  1:17.365 + 1.615   23
20.  Sutil         Force India-Ferrari (B)  1:17.612 + 1.862   21

All timing unofficial