(CNN) -- Sebastian Vettel set the fastest time in in free practice ahead of Sunday's Canadian Grand Prix in Montreal.
Reigning world champion Jenson Button in his McLaren was quickest in first practice on Friday, but the afternoon session was substantially faster at the Gilles Villeneuve circuit.
Germany's Vettel lapped in one minute 16.877, just eight hundredths of a second quicker than two-time world champion Fernando Alonso of Spain in his Ferrari.
Mercedes driver Nico Rosberg of Germany was third best followed by the Red Bull of title leader Australia's Mark Webber.
Felipe Massa was fifth quickest in the second Ferrari, closely followed by Force India driver Adrian Sutil.
Lewis Hamilton, third best in the morning session, came next for McLaren ahead of Renault's Robert Kubica.
Germany's Michael Schumacher, second in the morning runs, was ninth fastest in the second Mercedes.
McLaren go into the race hoping to repeat their 1-2 in Turkey where Hamilton won from Button to revive his championship hopes.
The Red Bulls had been leading until Vettel collided with a furious Webber, who had to pit and settle for third place.
The McLarens are sporting the 'F-duct' aerodynamic device, which is tipped to help them on the street circuit with its long straights and tight corners.
Qualifying to decide grid positions for the race takes place on Saturday.