Toronto, June 13 : A clutch birdie three on the penultimate hole proved the difference for Rory McIlroy on Sunday as the Northern Irishman successfully defended his RBC Canadian Open title with a two-stroke win at St. George's Golf and Country Club. The world No. 8 demonstrated why he is one of the favorites going into next week's U.S. Open at Brookline when he closed with an eight-under 62 to finish on -19 under 261. The victory was worth 1.566 million U.S. dollars. Tony Finau, the overnight co-leader with McIlroy, snaked in a long birdie putt at the last for a 64 to finish runner-up. Fellow American Justin Thomas (64) was third at four strokes off the pace. Englishman Justin Rose made a bogey at the last and had to settle for a tournament-low round of 10-under 60 to finish equal fourth with American Sam Burns (65). Corey Connor was the top Canadian at his national Open, closing with a 62 to finish sixth. American Wyndham Clark, the leader through the first two rounds, carded a 69 to tie for equal seventh with compatriots Chris Kirk (66) and Keith Mitchell (66). World No. 1 Scottie Scheffler shot a 66 for his best round of the week to sit 12 strokes back in equal 18th. With McIlroy dropping a shot at the 16th hole and Thomas making par, the two top draws were deadlocked for the lead on 17-under with two holes to play. At the 494-yard, par-four next, McIlroy put his approach to within three feet of the flag from 125 yards out while Thomas' approach was short of the green. As Thomas would take three more shots to get into the hole McIlroy converted his birdie putt for a two-shot swing. Thomas would also bogey the last as Finau, the final group's other player, sank a 42-foot birdie putt to claim the runner-up honor. McIlroy birdied the final hole in his round that featured nine more birdies and two bogeys. The victory was McIlroy's 21st PGA Tour title, moving him into equal 31st on the all-time tour wins list. "One more than Norman," noted McIlroy with a wry smile, the remark a subtle jab at Greg Norman, the former World No. 1 who is now CEO of the upstart LIV Invitational Series. The Saudi-backed circuit launched this week with aims to rival the PGA Tour. "I feel like it's getting tougher and tougher to win on the PGA Tour. Just look at the two guys that I played with today. I went out with a lead and had to shoot eight-under-par to get the job done. The depth of talent on this tour is really impressive." McIlroy called his title defense in Canada great preparation for next week when he will attempt to win his fifth Major at the U.S. Open. His last Major victory came in 2014 at the PGA Championship. Earlier this year he was runner-up to Scheffler at the Masters. "There's no better way to prepare yourself for tournament golf than to be in contention, having to hit the shots when you need to. I proved this week that I can do that and hopefully get myself back into position to have to do that again next week." Finau, a two-time winner on the PGA Tour, carded a bogey-free round featuring six birdies, reports Xinhua. "We were within one there going to the last couple, so I knew I had an opportunity in front of me. But Rory played great, he closed it out and hat's off to him on a week like this." The Utah native said his form was good going into Brookline, a course he had never played. "Any time you're coming off a good solid performance, no matter what you place, it always gives you confidence. It definitely has given me confidence this week." /IANS