Sebastian Vettel led a Ferrari one-two in final practice for the Canadian Grand Prix.
Lewis Hamilton's Mercedes team have a new engine for this weekend's race at the Circuit Gilles Villeneuve, but Ferrari's straight-line speed advantage puts them in a strong position to fight for pole later on Saturday.
Hamilton finished third, four tenths of a second adrift of Vettel's impressive pace. Valtteri Bottas was fourth, over half-a-second slower than the Ferrari driver.
Ferrari have struggled to contend with Mercedes this season, but their pace in the final running before qualifying will give them hope they can take the fight to the sport's all-conquering team.
Hamilton was forced to watch the majority of Friday's second session on the sidelines after he crashed out, the world champion sustaining extensive damage to his Mercedes.
But Hamilton was back in action on Saturday morning, finishing three tenths quicker than Bottas in the sister Mercedes.
The championship leader, however, is set to face a serious challenge from Ferrari in the shootout for pole.
The under-performing Scuderia have not won a race this season, while Vettel is without a victory since last August's Belgian Grand Prix.
Elsewhere, Max Verstappen and Pierre Gasly finished fifth and sixth respectively for Red Bull. British teenager Lando Norris was eighth for McLaren.
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