Pettersson's 67 was seven strokes higher than his score Saturday, but still good enough for win.
TORONTO (AP) -- Carl Pettersson rallied to win the Canadian Open on Sunday for his fourth PGA Tour victory, following his tournament-record 60 with a 3-under 67 for a one-stroke victory over Dean Wilson.
Pettersson, the 32-year-old Swede who went to high school and college in North Carolina, finished at 14-under 266 at hilly, tree-lined St. George's.
"I still can't believe I won the tournament," Pettersson said two days after making the cut by a stroke after opening rounds of 71 and 68. "I know it's difficult to shoot another low one after a round like that, so I was just trying to downplay it. I just tried to stay calm and (said), 'Whatever happens today, happens.'"
The 40-year-old Wilson, playing on a sponsor exemption, shot a 72 after opening with three straight 65s to take a four-stroke lead into the final day.
"If you would have told me before the week that I could be second alone, I would have been tickled," Wilson said. "Being in the position that I was, I'm a little disappointed. But still, lots of positives."
Six strokes behind Wilson after seven holes and four back with seven to play, Pettersson made a 15-foot birdie putt on the par-3 13th to pull within one, then took the lead with a 25-footer from the fringe on the 480-yard, par-4 14th.
Wilson bogeyed 14, hitting into the thick rough to the right of the green, chipping through the putting surface to the opposite fringe and missing a 15-foot par try.
"That was my bad swing of the day," Wilson said. "I had a good yardage, good mindset on what I was going to do and I just didn't execute. I caught that ball a little thin and it rolled through the green. And I paid the price in that rough."
Pettersson pulled away on the par-5 15th with his third straight birdie and fourth in five holes, hitting a wedge to 4½ feet. Wilson's approach trickled into the back fringe and his birdie try came up 2½ feet short.
Pettersson parred 16 and 17 and, with a shot to spare, bogeyed the 18th, missing a 5-foot par putt after Wilson putted out for his fourth straight par.
"I felt like I handled it well coming in," Pettersson said. "I know I bogeyed the last, but after Dean didn't make birdie, I sort of ginched that putt up there."
Pettersson bogeyed the par-4 seventh to fall six strokes behind Wilson, then birdied Nos. 8 and 9 to cut the margin to four before seizing control on the back nine.
"I was just the sideshow on the front nine," Pettersson said. "I just love that back nine. It sets up great for me."
The former North Carolina State player earned $918,000 for his first victory since the 2008 Wyndham Championship. He also won the 2005 Chrysler Championship and 2006 Memorial.
Luke Donald (66) was third at 12 under. Matt Kuchar (67), Bryce Molder (70), Bob Estes (71) and Tim Clark (71) were part of a large group that finished at 10 under.