Portuguese GP - Stoner quickest out of the blocks

Casey Stoner left all his Moto GP rivals with furrowed brows yet again as he set the pace in the first free practice session for the Portuguese Grand Prix.

As usual the 21-year-old Australian, who can be crowned world champion if results go his way at Estoril this weekend, was in imperious form from the get-go and lapped the track in 1:38.105 on his Ducati.

Valentino Rossi, who needs to finish at least fifth to take the title battle to another race, was second quickest on his Yamaha, which was again running the pneumatic engine that failed at Misano, 0.312 seconds slower.

His lap though, which was set late in the session, showed the gains that Michelin have made on tyre rivals Bridgestone, who supply Stoner's bike, since the Misano race two weeks ago.

Randy de Puniet was third fastest on his Bridgestone-shod Kawasaki with Colin Edwards' Yamaha and Carlos Checa's LCR Honda - both on Michelins - completing the top five.

John Hopkins was sixth quickest on the best of the Suzukis with Repsol Honda duo Dani Pedrosa and soon-to-be former world champion Nicky Hayden next up.

Shinya Nakano was ninth quickest on his Konica Minolta Honda while Marco Melandri, who has yet to shake off neck and ankle injuries sustained in recent races, completed the top ten for Gresini Honda.

Melandri's Gresini team-mate Toni Elias, who won the race last year, was only 14th quickest.