McLaren-Mercedes Formula One driver Jenson Button scored a stunning win in Sunday’s wild, rain-hit Canadian Grand Prix in Montreal after leader Sebastian Vettel made a big mistake on the final lap.

Button recovered from a drive-through penalty and two collisions earlier in the race that both resulted in pit stops to replace punctured rear tires.

Rain came as expected on Sunday, and the opening laps ran behind a safety car before race officials released the drivers. Vettel led away from pole while further back, Lewis Hamilton tangled with Mark Webber at turn one, pitching the Red Bull Racing driver into a spin.

Not long after, Hamilton--trying to recover lost ground--pulled alongside teammate Button on the pit straight on lap seven. Button apparently didn’t see his teammate, and the two made contact at high speed. It could have been a crash of aircraft proportions, but Button escaped with a puncture while Hamilton retired with suspension damage.

The rain returned later, forcing another safety-car interlude and then a red flag. The cars sat on the grid for two hours, through some more heavy storms, before race control deemed the track dry enough to resume, initially behind the safety car once again.

When the race restarted for real, drivers began pitting for intermediate tires, and then Button got into trouble again when he hit Fernando Alonso, pitching the Ferrari driver out of the race. That created yet another safety-car period, and Button was able to pit to replace another punctured tire.

After another restart, the race came alive once more as slick tires became an option as a dry line emerged on the track. Button found his car working superbly in the still-tricky conditions, and he put his head down and gained positions quickly.

In the closing laps he reeled in Vettel, who led throughout the day only to lose his advantage over his rivals every time officials deployed the safety car. The gap between the Red Bull and the McLaren shrank with each lap, and going into the last lap, Button was right with the reigning world champion. When Vettel had a half spin under pressure that took him off and back on the road, the 2009 champion pounced and seized the lead.

Button afterward made the understatement of the day when he said, “It had its ups and downs, let’s just say that. Definitely one of those Grands Prix where you are nowhere, then you’re somewhere, then you’re nowhere and then you’re somewhere. As we always say, the last lap is the important one to be leading, and I was leading half of it. It really is an amazing day and I don’t know what else to say, really.”

Webber recovered from his first-lap incident to claim third, while Michael Schumacher had the best race of his F1 comeback to claim fourth. Schumacher was the fastest driver on the track with a few laps to go and ran as high as second before he ran out of momentum and was passed by Button and Webber.

Vitaly Petrov did well to claim fifth for Renault, while Felipe Massa earned Ferrari its only points with sixth after running in the top three for much of the race until he damaged his nose in an incident.

The top 10 was completed by Sauber’s Kamui Kobayashi--who did a great job to run in second place before the red flag halted the event—Scuderia Toro Rosso’s Jaime Alguersuari, Williams driver Rubens Barrichello and Toro Rosso’s Sébastien Buemi.