Justin Thomas survived a "disaster" at the 72nd hole before beating Patrick Reed and Xander Schauffele in a three-way playoff at the PGA Tour's Sentry Tournament of Champions in windswept Hawaii on Sunday.

Thomas clinched victory with a three-foot birdie at the third extra hole, the par-five 18th, at the Kapalua Plantation course on Maui.

Schauffele was eliminated at the first hole of sudden death while Reed fell two holes later as the 26-year-old Thomas earned his 12th PGA Tour victory.

He had one hand on the trophy with a one-shot lead playing the final hole of regulation but hooked his three-wood second shot into a penalty area and could not find his ball in the waist-high tropical grass.

He made a bogey for a four-under-par 69, while Schauffele had a three-putt par, missing a seven-footer for the win, and carded 70.

They fell into a playoff with Reed, who earlier shot 66, at 14-under 278. 

"For some reason I was supposed to win this week," Thomas said in a greenside interview after sinking his winning putt in semi-darkness.

"I got very, very lucky to even have that putt. I got very fortunate, but I also stuck to my process and tried to stay positive.

"Through 15 holes it was one of the best rounds I've ever played. I was in such control, tee to green, putting beautiful, my irons were awesome and then 18 was a disaster. It worked out so I can't complain."

Reed three-putted the second extra hole from the fringe and then missed an eight-foot birdie at the third playoff hole, his mood hardly helped when a spectator screamed "cheater" as his ball slid by the hole.

Reed has been in the spotlight since being hit with a two-stroke penalty for improving his lie in a waste bunker during last month's Hero World Challenge in the Bahamas.

Schauffele, who had been on the verge of successfully defending his title, said: "I should have won it.
"I know it, everyone knows it. I should have closed it out and didn't.

"I kind of did everything I was supposed to until the last moment.