Charles Leclerc led a Ferrari one-two in second practice at the Canadian Grand Prix after Lewis Hamilton crashed his Mercedes.
Leclerc and team-mate Sebastian Vettel, who had been lagging behind the Mercedes, leapt to the top of the times on their qualifying simulation runs.
Leclerc edged Vettel by 0.074 seconds, after improving on his second attempt.
Mercedes' Valtteri Bottas was 0.134secs adrift in third. Hamilton was sixth after the crash curtailed his running.
The world champion had been quickest when he lost control in the chicane at Turns Eight and Nine, losing the rear and clouting the concrete wall on the outside of the track.
He managed to return to the pits despite a punctured tyre but the incident damaged his car's floor. Mercedes changed the rear end of the car as a precaution but they were unable to get him out in time to take any further part in the session.
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Hamilton said: "I made a mistake and damaged the car. The boys tried really hard to fix it, but there wasn't enough time.
"I don't remember the last time I missed a whole session before. It's definitely not great to watch the session from the garage. It feels like sitting in the headmaster's office, wishing to be back in class.
"It was an innocent mistake. I was doing multiple laps on the medium tyre and was really trying to find the limit. Obviously I went slightly over. I had a big snap out of Turn Nine and was drifting for a long time, hoping I wouldn't hit the wall. But these things happen. You just have to put it behind straight away you and get back on the horse.
"Luckily Valtteri had a good session today, so there'll be a lot of analysis from that."
Ferrari had looked off the pace throughout first practice and through the first runs of the second session, lagging a second or so behind the Mercedes.
But Vettel went fastest on his first lap on low fuel and soft tyres midway through the session. The four-time champion was just just over 0.1secs quicker than Leclerc after their first laps, but the Monegasque improved on his second while Vettel could only repeat his first lap time.
Vettel said: "Not a great day in terms of tyres because they didn't last very long, the very soft compound.
"Overall it was not so bad but we certainly need to improve if we want to put the car in a good position for the race because we're not the fastest. It might look like that if you look at the one-lap performance but I think there is still quite a reasonable gap to Mercedes."
Mercedes have won all the first six races but Ferrari were expected to be more competitive in Canada because the track's layout - comprised of long straights and slow corners - plays to the strengths of their car.
In that sense, it is similar to Bahrain and Azerbaijan, both of which Ferrari could have won if they had not run into problems.
Red Bull's Max Verstappen, who had been close behind the Ferraris earlier in the session, clipped the wall in the final chicane on his fastest lap, as he lost front grip close behind his team-mate Pierre Gasly. The Dutchman ended up 13th, one place ahead of the Frenchman.
McLaren's Carlos Sainz was a highly impressive fourth quickest, just 0.376secs off the pace and 0.382secs ahead of the Haas of Kevin Magnussen in fifth.
Sainz's team-mate, the British rookie Lando Norris, was 11th.
"I think we had one of the best Fridays of the season but I don't believe we are fourth fastest," said Sainz. "We are behind the top three teams. Tomorrow will be back to reality."
Sainz's strong progress continued on his race-simulation run, which was considerably quicker than Vettel's on the same soft tyre, although all drivers were struggling with overheating and the tyres were losing pace very quickly.
But it was Bottas who set the pace on race-distance lap time. His long run on the soft was just over 0.6secs quicker on average than Sainz, as the drivers and teams struggled to understand how the tyres will behave in race conditions.
Behind Hamilton, Racing Point's Sergio Perez was seventh, ahead of the Renaults of Daniel Ricciardo and Nico Hulkenberg and Perez's team-mate Lance Stroll.
Less than a second covered the top 10 cars - and less than two the top 17.
The other British driver George Russell was 19th, his Williams team well off the back of the field as usual. Russell just under 0.3secs quicker than team-mate Robert Kubica, who did not take part in the first session as his car was being used by reserve driver Nicholas Latifi.