MONTREAL -- Carl Edwards passed Marcos Ambrose on the final turn to win the crash-filled Nationwide race at Circuit Gilles Villeneuve, which ended with the cars on rain tires for the second straight year.
Edwards won a two-lap sprint to the finish on a track that was both wet and dry in spots from a light rain when Ambrose, who dominated the race, slid sideways after hitting the rumble strips in Turn 14. Edwards slipped past Ambrose and outraced him down the final straightaway for his first career road win and the first for Roush Fenway Racing.
"The difference was the tires and the way the track was changing," Edwards said. "As soon as it gets dry, there's so much more grip, and there were places out there I saw that had a little more grip. Maybe I could just see better through my windshield."
Ambrose survived three other restarts in the final 11 laps of the race, which was plagued by 11 cautions and went an extra lap.
"I made a mistake at the end there and just lost it," Ambrose said. "Carl put pressure on in the hairpin. He got a great run, and it turned into a drag race. I couldn't make the turn, bounced off the curb, and Carl slingshotted the corner. When you're on the wrong side of it, it's pretty tough."
Ambrose was out to right what went wrong in the previous two Nationwide races at Circuit Gilles Villeneuve. In 2007 he led 37 laps and was challenging for the win before he was spun out by Robby Gordon and finished seventh.
Last year in the rain, Ambrose led 27 laps but was caught speeding on pit road late in the race and Ron Fellows won the rain-shortened event, the first points race in NASCAR history to be run on rain tires.
NASCAR Canadian Tire Series star Andrew Ranger was third. Former Formula One star Jacques Villeneuve finished fourth on the track named for his father, and Brad Keselowski was fifth.
Points leader Kyle Busch went from fourth to 10th on the final two laps.
Ambrose started from the pole and was out front most of the race. He led 60 laps -- including 31 in a row when rain moved in for the second year in a row. The crowd cheered when the red flag flew, stopping the race at the end of Lap 61 so the teams could switch to rain tires, slap on windshield wipers, and hook up brake lights in a five-minute window.
The red flag lasted 6 minutes, 51 seconds, and the 74-lap race resumed on Lap 64 with the 2.7-mile, 14-turn course damp but with no standing water like a year ago.
Ambrose quickly cleared Ranger's second-place car. Edwards then tangled with Ranger and Busch slipped past both for second, with Edwards and Ranger right behind.
Ambrose had a 2.8-second lead after the first time around, but the ninth caution of the race, for debris, erased that margin on the next lap.
Ambrose again assumed control when the race went green again on Lap 68, but several cars spun out before the 31 cars remaining in the race made a complete trip around. That brought out caution No. 10.
Ambrose easily drew clear on the restart on Lap 71 and Ranger passed Busch for second. But Steve Wallace set up a two-lap dash to the finish when he made contact with Victor Gonzalez and slid sideways into a big pack in the second turn to bring out the race-changing final caution.