Sebastian Vettel has ended the final practice session from the Circuit Gilles Villeneuve in first place, laying down a 1:10.843 on the soft tyres.
The German was over one-tenth ahead of teammate Charles Leclerc, as the two traded fastest laps during the session in search of more lap time.
Ferrari has indicated that Canada is the team's best opportunity to beat Mercedes since Bahrain, where it locked out the front row.
The Maranello squad may be encouraged after the FP3 session, as Mercedes ended up just under four-tenths down on Vettel, as Lewis Hamilton was third on the timesheets.
Valtteri Bottas was a little further down, while Red Bull was far off the pace, despite Max Verstappen stating on Friday that the gap between Red Bull and the leaders was "not dramatic".
However, Verstappen's fast lap was hampered as he got held up in the final sector by Hamilton. Gasly was less than one-tenth down on his teammate's time.
Daniel Ricciardo was hoping to get in front of McLaren for qualifying, and managed to do so in the final practice session, as the Australian was a tenth faster than Lando Norris.
Racing Point and Toro Rosso also got into the top ten, as Sergio Perez set the ninth fastest time ahead of Daniil Kvyat, who rounded out the top half of the grid.
Lance Stroll's practice session came to an early end when he ground to a halt in the pit lane with a suspected hydraulics leak.
The Racing Point team is working on the car with the hope of getting Stroll back out onto the track for qualifying at his home event. The Canadian will be searching to end his run of consecutive Q1 dropouts.
Qualifying gets underway in a couple hours time, with Ferrari looking to get on top of Mercedes, who has dominated the season up to this point, taking all six victories on offer in 2019.