Jenson Button (photo) has topped the first practice session for the Canadian Grand Prix, edging Michael Schumacher by 0.158 seconds.

Button, a two-time winner this season for McLaren after winning the world championship last year for Brawn GP, had a fastest lap of 1 minute, 18.127 seconds yesterday on the 4.4-kilometre Circuit Gilles Villeneuve.

Schumacher, the seven-time world champion driving for Mercedes GP after a three-year retirement, has seven victories in Montreal.

McLaren’s Lewis Hamilton, coming off a victory in Turkey, was third – 0.225 seconds back. He won in 2007 in Montreal.