Heidfeld on top in final Belgian GP practice

Germany's Nick Heidfeld put BMW-Sauber on top of the timesheets in final Belgian Grand Prix free practice.

Heidfeld, under pressure to raise his game at a team yet to confirm their 2009 lineup, completed 18 laps of Formula One's longest circuit with a quickest time of one minute, 47.876 seconds.

McLaren's Heikki Kovalainen was second quickest, 0.289 slower, on a cold and damp morning with the constant threat of rain in the Ardennes forests.

Renault's double world champion Fernando Alonso was third ahead of McLaren's overall leader Lewis Hamilton and Ferrari's Brazilian Felipe Massa.

Hamilton leads Massa by six points with six races remaining, including tomorrow.

Ferrari's world champion Kimi Raikkonen, winner of the last three Belgian Grands Prix but without a victory since April and now 13 points adrift of Hamilton, was seventh quickest.

Heidfeld's best time, which came right at the end of the hour-long session, was slower than Massa's quickest lap in Friday's first practice.

Honda had another nightmare morning, with Briton Jenson Button pulling over at the first corner of his opening lap while Brazilian team mate Rubens Barrichello was the slowest driver on the circuit.