Championship leader Sebastian Vettel laid down an ominous marker to Lewis Hamilton after he stormed to the top of the timesheets in final practice for the Canadian Grand Prix.
Vettel, who holds a 25-point lead over Hamilton in the title race, ended the session at Montreal's Circuit Gilles Villeneuve more than a third of a second clear of the Mercedes driver.
Indeed Hamilton, a winner in Canada on five occasions and seeking one further pole position to match his childhood hero Ayrton Senna, had to settle for third on Saturday morning with Kimi Raikkonen slotting in behind his Ferrari team-mate.
Ferrari secured their first front-row lockout in nearly a decade at the last round in Monaco - and on this morning's evidence at least - would once more appear to hold a clear advantage over Hamilton's Mercedes team ahead of qualifying later on Saturday.
Vettel's impressive lap of one minute and 12.572 seconds was enough to finish nearly three tenths ahead of Raikkonen with Hamilton 0.354 sec off the pace. Valtteri Bottas, in the sister Mercedes, was fifth in the order behind Red Bull's Max Verstappen.
McLaren's Fernando Alonso saw his return to the Formula One paddock plagued by further reliability issues on Friday, but a clear run for the 35-year-old Spaniard placed him 12th in the running.
British driver Jolyon Palmer was 15th, more than half a second adrift of his Renault team-mate Nico Hulkenberg who finished sixth, while Lance Stroll - the 18-year-old rookie whose motor racing career has been bankrolled by his fashion billionaire father Lawrence - was only a lowly 18th in front of his home crowd.
Meanwhile, a one-minute silence will be observed ahead of tomorrow's race in memory of those killed and injured in last Saturday's terror attack in London.
Canadian Christine Archibald, who hailed from British Colombia, was the first victim to be named after the attack and the promoters of this weekend's Montreal race have called on Formula One to hold the tribute in her honour.
British team Williams are also running #London on the front of their cars.