McIlroy had his first title defense on the PGA Tour, even if he had to wait for it. He won golf's fourth-oldest national open in 2019 at Hamilton Golf & Country Club, only for the the COVID-19 pandemic to cancel the next two editions.
Thomas pushed him to the end at St. George's Golf & Country Club, and the tournament effectively ended on the 17th hole. McIlroy and Thomas were tied and in the rough. McIlroy hit a wedge that rolled out to tap-in range, while Thomas missed a 10-foot par putt, a two-shot swing. Thomas closed with a pair of bogeys and still shot 64.
McIlroy finished at 19-under 261 for a two-stroke victory.
"I feel like it's getting tougher and tougher to win on the PGA Tour," McIlroy said. "Just look at the two guys that I played with today. I went out with a lead and had to shoot 8-under par to get the job done. So the depth of talent on this tour is really, really impressive. And going up against guys like J.T. and Tony and coming out on top, that's something to feel really good about."
Finau holed a 40-foot birdie putt on the 18th for a 64 to finish second alone.
"Rory played great," Finau said. "He closed it out and hat's off to him on a week like this. That's fantastic playing on the weekend. I played great, he just played a couple shots better."
A week before the U.S. Open, the Canadian crowd was enormous having been kept away since 2019, and thousands surrounded the 18th green as the threesome of McIlroy, Thomas and Finau finished.
"It was really cool to be a part of and just really happy to get the win today and obviously sets me up well going into next week in Boston," McIlroy said. "But right now I just want to enjoy this and focus on this."
McIlroy won for the second time this season, adding to his October win in Las Vegas in the CJ Cup. He won for the 21st time on the PGA Tour.
"This is a day I'll remember for a long, long time," McIlroy said soon after the victory.
Rose was 11 under with three holes to play. He bogeyed the 16th, hit to 2 feet on 17 for birdie, then went over the green on 18 and missed an 18-foot par putt. Carl Pettersson also shot 60 at St. George's in his 2010 victory.
"I'm totally disappointed, because you know what's at stake, for sure," Rose said. "I never shot 59 before, so it would have been a lovely footnote on the week."
He regretted hitting an 8-iron instead of a 9-iron on 18 with 159 yards to the pin.
"I don't know how much was in my control or not, but we were right in between two clubs and I went the wrong way on a decision and paid the price for it," he said.
Corey Conners was the top Canadian, shooting a 62 to finish sixth at 12 under.
"Felt like the last few days I played really solidly," Conners said. "Just last few weeks even, just hadn't maximized the game, hadn't got as much out of the game as I wanted. Definitely, nice to have low round today. Played really well. Definitely, felt it coming."