Max Verstappen overcame the weather and capitalised on a well-timed safety car to thwart Lando Norris and George Russell and win an action-packed Canadian Grand Prix.
Norris came alive in changeable conditions to take the lead having started third but, in a role reversal from Miami, was undone by the timing of the safety car and had to settle for second.
Pole-sitter Russell endured an incident-filled race but saw off team-mate Lewis Hamilton in the closing stages to claim Mercedes' first podium of the season.
Russell took pole having set an identical time to Verstappen during a thrilling qualifying session on Saturday, where the top seven were separated by less than three tenths of a second.
Heavy rain began around 90 minutes before the start and 18 of the 20 cars began on intermediate tyres - with Haas pair Kevin Magnussen and Nico Hulkenberg on wet rubber from 14th and 17th on the grid.
The leaders tiptoed into turn one and the top four retained positions as Russell led Verstappen.
Magnussen and Hulkenberg were flying and by the seventh lap the Dane charged past Oscar Piastri to take fourth while his team-mate was up nine places to eighth.
Their joy was short-lived as the rain eased, with Magnussen having to pit on lap eight.
Monaco winner Charles Leclerc, who started 11th after a miserable qualifying for Ferrari, was told he had an engine issue which was costing him half-a-second a lap.
Daniel Ricciardo, an impressive fifth on the grid, was hit with a five-second penalty for a false start.
The sun came out and, as the track dried rapidly, it was Verstappen who lit up the timing screens and climbed all over the back of Russell.
But the three-time world champion ran across the kerbs at turn one, putting himself under the cosh from the fast-moving Norris.
The McLaren driver blasted past Verstappen with DRS on lap 20 and quickly dispatched compatriot Russell - with the Mercedes driver then running off track at the final chicane allowing the Dutchman to also charge through.
Norris blasted to an eight-second lead but that was snatched away when Logan Sargeant hit the wall and a safety car was deployed.
Norris was hugely disadvantaged as Verstappen and Russell pitted ahead of him and the 24-year-old rejoined third.
Verstappen's engineer told him "what goes around comes around" - a reference to Norris being aided by a safety car to beat the Dutchman in Miami.
Ferrari put Leclerc on slick tyres just as the rain returned and racing restarted. The Monegasque crawled back to pits two laps later, was soon lapped by the leaders and retired on lap 43.
Seven-time world champion Hamilton pulled the trigger and pitted for slick medium tyres from fifth.
Two laps later, Norris was the only car to stay out on intermediate tyres as McLaren rolled the dice.
It was almost a brilliant move as Norris rejoined level with leader Verstappen but had no grip on the pit exit as the world champion stayed ahead.
Russell charged past Norris again with 20 laps to go but two laps later they changed positions again as the pole-sitter ran wide.
"Focus George, focus," Mercedes boss Toto Wolff urged on the radio.
The drama was only just beginning as Sergio Perez slid into the wall before Carlos Sainz spun into Alex Albon, dumping the Williams driver into the wall and bringing out a second safety car with 16 laps to go.
Russell and Hamilton pitted for fresh tyres as the top three stayed out. The safety car ended to leave an 11-lap dash to the chequered flag.
Russell and Oscar Piastri collided at the final chicane, with Russell dropping back behind team-mate Hamilton.
But Russell was not to be undone by his team-mate and charged past again to cap off a thrilling race at Circuit Gilles Villeneuve as Verstappen extended his championship lead.
"What a race, guys. Not easy but we did it," Verstappen said.
Norris said: "It was chaos, eventful. I felt like I drove a good race. The safety car had me over. It helped me in Miami but now it's had me over. It happens."
Russell added: "It felt like a missed opportunity, to be honest. Made a couple of mistakes out there pushing the limits. We will take positives from this weekend. Exciting moving forward."
