Austin - Two-time Masters champion Bubba Watson won the WGC Match Play Championship on Sunday, routing Kevin Kisner 7&6 in the final after denying Justin Thomas the world No 1 ranking in the semi-finals.
The 39-year-old American joined Tiger Woods, Rory McIlroy, Phil Mickelson and Ernie Els as the only players with multiple major and WGC wins, his other WGC crown coming in China at the 2014 HSBC Champions.
Watson, the 35th seed, won the first five holes of the final and never looked back in taking his 11th PGA title and second of the year after winning last month at Riviera.
"I got off to a good start, really got it going," Watson said. "There were only about four or five shots over the whole week where I lost my focus, where I didn't have my concentration."
His win came with the start of the Masters, the year's first major event which he won in 2012 and 2014, looming on April 5 and Watson confident as he heads for Augusta National.
"It comes from knowing I've got strength to hit the shots again," Watson said.
"Physical strength, being healthy, is going to create the mind - you're going to have confidence."
In the semi-finals, Watson defeated second-seeded compatriot Thomas 3&2 and 32nd-seeded American Kisner beat Sweden's Alex Noren in 19 holes at Austin Country Club.
"I didn't really make any mistakes," Watson said.
"And then I made some putts early. You have a chance to get the lead. I played solid and he didn't make any putts."
Thomas, who won his first major at last year's PGA Championship, was chasing his fifth title in eight months and would have overtaken American Dustin Johnson atop Monday's world rankings by winning, Johnson having crashed out in the group stage.
"It might be a good thing going into Augusta not to deal with all that and let DJ have all that pressure," Thomas said.
Thomas admitted the chance to match Woods and Jordan Spieth as a world number one before age 25 weighed on him.
"I haven't had such a hard time not thinking about something so much. And that really sucked. I couldn't stop thinking about it," Thomas said.
"You're constantly getting questions about it with the media but I need to be mentally stronger than that, and understand that it's just a match.
"At the end of the day, obviously I didn't play very well, but I definitely didn't give him the match. He made a lot of birdies and played well enough to be deserving to be in the final match."
Watson sank a 12-foot birdie to win the first hole against Kisner. At the second, Kisner missed a nine-footer for par, falling 2-down for the first time all week.
Bogeys by Kisner at the par-5 third and par-3 fourth staked Watson a 4-up lead and a concession birdie by bogey-bound Kisner followed at five.
Kisner sank a 12-foot par putt to avoid losing the par-5 sixth but took three to reach the green at the par-3 seventh to fall 6-down.
Watson sank an 11-foot birdie putt at 10 but Kisner, on the brink of defeat, rolled in a 34-foot birdie at the par-3 11th to win his first hole.
But that only delayed his fate, Watson capturing the crown with a seven-foot birdie putt at the par-5 12th.
"It's just one of those deals. Every time I looked up, there was nowhere to look," Kisner said.
"I guess I need to figure out what happened this afternoon and work on that."
Kisner was chasing the biggest title of his career, having won PGA crowns at Colonial last year and Sea Island in 2015.
Kisner showed grit in the semi-final, making an eagle at 12 to square with Noren, then matched him with six birdied in a row before sinking a five-foot birdie putt on the first extra hole, the 12th, to dispatch Noren.
"That was a tough match," Kisner said.
"He kept hitting it in there close. I hung in there and made putts and got it done in the playoff."
Noren beat Thomas 5&3 for third place.
Results from Sunday's matches at the World Golf Championships Match Play Championship in Austin, Texas (x denotes seeding):
Bubba Watson (USA x35) bt Kevin Kisner (USA x32) 7&6
Alex Noren (SWE x13) bt Justin Thomas (USA x2) 5&3
Bubba Watson (USA x35) bt Justin Thomas (USA x2) 3&2
Kevin Kisner (USA x32) bt Alex Noren (SWE x13) 19 holes