Reed closed with a four-under 68 at Torrey Pines on Sunday, making an eagle on the par-5 6th and finishing off his ninth PGA Tour title with a birdie on the 18th as he finished 14 under.

Tony Finau (69), Xander Schauffele (69), Ryan Palmer (70), Sweden's Henrik Norlander (69) and young Norwegian star Viktor Hovland (71) all tied for second.

Australia's Adam Scott went backwards with a 73, including four bogeys, to finish tied 10th, seven shots behind fellow former Masters champion Reed.

Marc Leishman was the next best Australian, tied 18th after a 70 while Cameron Davis (73) tied 32nd, Cameron Percy (72) and Matt Jones (71) tied 48th on even par and Rhein Gibson (74) was a shot further back.

Reed had been cleared by the PGA Tour over a controversy that erupted on Saturday when he picked up his ball to see if it was embedded before a rules official arrived and he received a free drop.

Replays showed Reed's ball had bounced before sinking into deep rough, which he later admitted would suggest it didn't embed, but no one was aware of that at the time.

"My biggest takeaway was mentally, I hung in there and stayed the course." – Patrick Reed

Reed, who has had rules-related issues in the past, including at the 2019 Hero World Challenge, faced several media questions about it afterward and said he believed he handled the matter properly, given what he knew. Tour officials agreed.

"My biggest takeaway was mentally, I hung in there and stayed the course," Reed said after his victory.

"... We felt like we did (the right thing), the rules officials felt like they did that at the same time so with that being said I felt fine, I felt great throughout the day. And at the end of the day, I wouldn't have felt any other way.

"I was able to shoot a low number (Sunday) and get the job done."

Sharing the lead overnight, Reed jump-started his final round with a 45-foot eagle putt on the 6th hole to get to 12 under and followed with a birdie on the par-4 7th.

His only bogey was on the par-3 8th, and he rebounded with a birdie on the par-5 9th. He played par the rest of the way until sinking an eight-foot birdie putt on No.18.

Joint overnight leader carlos Ortiz stumbled badly with a round of six-over 78 and tied 29th.