WGC Mexico Championship: Phil Mickelson defeats Justin Thomas on first playoff hole

The U.S. Open returns to Shinnecock Hills for the first time since 2004 with the expectation for a difficult challenge.

Phil Mickelson earned his first win Sunday since the 2013 Open Championship with a one-hole, sudden-death playoff win over Justin Thomas at the WGC Mexico Championship.

Mickelson, who became the oldest WGC winner, shot a final-round 5-under 66 to force a playoff at 16 under. Birdies on 15 and 16 helped Mickelson reach the playoff after Thomas posted an early number.

"To have the belief that I was going to get there and finally break through and do it feels incredible," Mickelson said after his round. I believe that more is to come."

Thomas, who shot a 9-under 62 Saturday to get back into contention, looked poised to add his ninth PGA Tour win when he holed out of eagle on the 72nd hole, but Mickelson fought from two shots down to force the playoff.

A win would have given Thomas three already this season, and eight since the beginning of last season.

Mickelson has his sights set on the Ryder Cup this fall, and he already has five top 10s this season, including four top 5s. With this week’s win, he will likely jump in position to be one of the eight automatic bids.

Tyrell Hatton and Rafa Cabrera Bello finished tied for third at 15 under. Hatton, after birdieing 14 and eagling 15, bogeyed 18 to fall out of the playoff. The Englishman has three European Tour wins.

Dustin Johnson and Sergio Garcia finished tied for seventh at 12 under. Johnson said he struggled with his putter this week, while Garcia was unable to get anything going in Round 4.

After impressing through three rounds, Shubhankar Sharma fell back into a tie for ninth at 10 under after a 3-over 74 on Sunday. Playing alongside Hatton and Mickelson Sunday, Sharma struggled to find the form that helped him lead through three rounds. This was his PGA Tour debut.