George Russell succeeded in claiming Mercedes' first pole position since Hungary in 2023, and he did so in a dead heat with Max Verstappen meaning the Red Bull will line up alongside him on the front row of the grid for tomorrow's Canadian GP.
Lando Norris was just two hundredths of a second further back, joining Oscar Piastri in an all-McLaren second row with Daniel Ricciardo a surprise P5 for RB ahead of Aston Martin's Fernando Alonso.
Ferrari pair Charles Leclerc and Carlos Sainz missed the second cut after trying to save a new set of soft tyres, while Red Bull's Sergio Perez was eliminated in the first round for the second race in a row.
After a gloomy and damp Friday at the Circuit Gilles-Villeneuve, Saturday had got off to an much better start with Lewis Hamilton and Max Verstappen topping a dry final practice. It gave the teams and drivers the dry running data they sorely needed, but just when everything looked set fair the weather radar showed a confusion of showers in the vicinity and an 80 per cent chance of rain. Anything could happen now in qualifying.
There had been some heavy showers since the end of FP3, but the warm weather meant the first round started on a dry track. Zhou Guanyu was first out in the Sauber having crashed twice already this weekend, with Verstappen also quick to get going.
His first run was six tenths slower than Lando Norris who had been quickest in FP1. The McLaren didn't spend long at the top before being displaced by local hero Lance Stroll in the Aston Martin and then by his team mate Fernando Alonso. George Russell confirmed the improved Mercedes pace by going top before Norris replied with a lap almost half a second quicker as track conditions evolved rapidly.
Stroll came within 0.002s of pipping Norris before double tapping the wall of champions without doing significant damage to the car. Verstappen went top on 1:13.368s and then it was Russell's turn again. Although the rain was holding off, traffic was a problem with Oscar Piastri and Sergio Perez among those languishing in the bottom five and at risk of missing the cut.
The cars came in for fresh tyres and headed back out for one last push. Hamilton went top on 1:12.851s and then Verstappen booked his place in Q2 with a new quickest time. RB's Yuki Tsunoda celebrated his just-announced contract extension by going P2 and both Williams drivers made it through. But Perez couldn't find the space he needed and missed the first cut for the second event in a row, along with Valtteri Bottas, Esteban Ocon, Nico Hulkenberg and Zhou Guanyu.
The first significant rain arrived as Q2 got underway meaning a mad scramble to set banker times before the track got too wet. Piastri jumped to the top with a time of 1:12.462s with Leclerc up to second, but both were swept aside by Russell's time of 1:12.323s.
Verstappen's first lap had left him outside the top ten and his next run was only good enough for P9, suggesting the changing conditions were making it harder for everyone. Everyone needed to go again, but there was panic at Williams with a cross-threaded wheel nut on Alex Albon's car that was only just resolved in time.
Russell had a scare in turn 4 and nearly hit the wall, which prompted the wholesome "oh, holy moly!" from the cockpit. Norris took advantage to go a tenth quicker at the top before Russell regrouped and went again to get back on top. Verstappen had managed to move into the safety of the top ten and suddenly it was Ferrari in trouble. Having gambled on a used set of softs to save a set for Q3, they ended up missing the cut instead - Ferrari's first failure to reach Q3 as a team since Spa 2021.
Both RBs of Tsunoda and Daniel Ricciardo had made it through as had Albon, but his Williams team mate Logan Sargeant joined the two Ferraris on the sidelines together with Haas' Kevin Magnussen and Alpine's Pierre Gasly.
The rain was still falling as Q3 got underway, but everyone was still on slicks as they headed out. Verstappen proved quick out of the box, his 1:12.358s putting him ahead of Piastri and Norris.
Russell and Hamilton bided their time in pit lane before finally making their move and it paid off with the two Mercedes going top, Russell the quicker of the pair by almost three tenths. McLaren were back out sooner than usual: Norris and Piastri improved to P2 and P3 but neither was able to topple Russell from provisional pole.
Mercedes held their cars back until the last possible minute despite the continuing threat of rain. Verstappen matched Russell's time of 1:12.000s leaving Russell with pole but taking a front row spot for himself ahead of the two McLarens. Ricciardo moved up to fifth ahead of Alonso, but Hamilton's final lap didn't find the time he needed to improve on P7 ahead of Tsunoda, Stroll and Albon.
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