George Russell edged out Max Verstappen to claim pole position for the Canadian Grand Prix. (More Motorsport News)
Russell and Verstappen, the reigning Formula One world champion and championship leader, set identical lap times.
Both clocked in at one minute and 12 seconds, but Russell was given the edge as he banked his first. That had not happened in F1 since 1997.
It is a huge boost for Mercedes, who seem to have turned a corner in recent races following some upgrades to their car.
"It's sort of come from nowhere," Russell said after qualifying in Montreal. "But maybe not a surprise with the upgrades we've been bringing.
"We brought these upgrades to Monaco, which has been a really challenging circuit for us in the past, and we were 0.1secs from the front row and we thought going into Montreal we had a shot here.
"It's just turning really nicely through the corners. We struggled a lot with understeer before.
"Last year, we had a lot of oversteer and we've been trying to find the halfway house between what we had last year and what we had this year.
"And it feels like we're sort of dialling in that sweet spot right now. So it feels like something we've been saying for a long time, in all honesty. But you know, just really a sense of relief to actually see it translate into a pole position. [There's] more to come.
"We are the favourite at the moment because we have the fastest car and I was feeling great behind the wheel.
"But there is rain on the horizon and the wind is picking up. We are going to have to be so on our feet. It's a bit of a shame in a way. But I am feeling optimistic."
Verstappen said: "It's how it is. We had a good qualifying. The whole weekend has been still a bit tricky for us but to be P2, I'll take it. Going into qualifying I would have definitely taken that. It makes it more exciting for the race as well."
Russell's team-mate Lewis Hamilton did not have as much luck, as he could only manage seventh place, behind the McLaren duo of Lando Norris and Oscar Pisastri.
Verstappen's Red Bull team-mate, Sergio Perez, also had a poor session, as he was knocked out in Q3 for the second straight race.
Perez's Red Bull future was confirmed this week, though the team are also keeping on Yuki Tsunoda as back up.
It was a poor day for Ferrari, with both Charles Leclerc and Carlos Sainz missing out on the top 10.
Sainz is hoping to claim a top seat for next season, with Hamilton replacing him at Ferrari, but Mercedes boss Toto Wolff confirmed that would not be with his team.
"Carlos deserves a top seat," Wolff said. "He's done a fantastic job, but for us we've embarked on a route now.
"We want to reinvent ourselves a little bit going forward and Kimi Antonelli definitely plays a part in that.
"We haven't taken a decision yet for next year but we didn't want to have Carlos wait as well because he needs to take decisions for himself and that's fair, but he's doing a super job."
