The 25-year-old German, who has finished on the podium in every race this year, lapped the French circuit in 1:21.895 with four minutes of qualifying remaining to knock his team-mate Andreas Zuber off the top spot.

Bruno Senna, the nephew of three-time Formula One world champion Ayrton Senna, will start third for Arden with Lucas di Grassi completing the second row for champions ART after spending the first half of the session on top.

Giorgio Pantano will start fifth for Campos but suffered a mechanical problem on his final flying lap which left him stranded in the middle of the circuit at the Lycee corner and almost saw Luca Filippi ram him from behind in his Super Nova car.

The pair had earlier been involved in an incident at the 180 hairpin as Filippi shoved his countryman into the gravel.

Roldan Rodriguez was a career-best sixth for Minardi-Piquet while Monaco winner Pastor Maldonado was seventh for Trident and Adrian Zaugg eighth in his Arden entry.

The DAMS cars of Kazuki Nakajima and Nicolas Lapierre completed the top ten, but the latter felt he could have gone faster had Javier Villa not got in his way at the Chateau d'Eau on a quick lap.

Throughout the session the gravel trap at Estoril proved popular with the drivers who were testing the limits of their machinery. Andy Soucek, Ernesto Viso, Xandi Negrao and Ho-Pin Tung all went off there.

And Karun Chandhok almost came a cropper too. Although he stayed on track, he had a lucky escape as he hit a bump on the exit of the corner, allowing air to get under his Durango car and lift his front end a foot off the ground.

British duo Mike Conway - who had a high-speed trip through the gravel at the Imola corner - and Adam Carroll will start 12th and 14th for Super Nova and FMS respectively.

- Jamie O'Leary -