ADAM Long of the United States kisses the trophy after winning the Desert Classic at the Stadium Course in La Quinta, California. AFP LONG NOW A WINNER

LA QUINTA, California — Adam Long bounced around golf’s backwoods for years, winning only a lone Hooters Tour event.

I’m in pretty disbelief right now. I don’t really know what happened

Now, he’s headed to the Masters as a PGA Tour winner.

Long won the Desert Classic on Sunday at PGA West, beating Hall of Famer Phil Mickelson and Adam Hadwin by a stroke with a 14-foot birdie putt on the final hole after a 6-iron approach from an awkward stance.

“In some ways it’s been a little bit of a roller-coaster, but it’s been a steady improvement throughout my career,” Long said.

“I’ve played in pretty much most tours around the world that there are and just kind of steadily progressed.”

“It kind of can seem like it came out of nowhere, but my game’s been trending in the right direction for really the last two years now.”

I had a terrible putting day — one of the worst I can recall in a while.

Long closed with a 7-under 65 on the Stadium Course, holing the winning putt after Mickelson’s 40-foot birdie try curled left at the end.

“I got a pretty good read off Phil’s putt,” Long said.

“It was one of those putts that you just stand over you just know you’re going to make.

And you can’t control that, but when you have that feeling it’s a good one. I’m in pretty disbelief right now. I don’t really know what happened.”

Mickelson, the leader after each of the first three rounds, shot 69.

“I had a terrible putting day — one of the worst I can recall in a while,” Mickelson said.

“Started right on the first hole with a little four-footer uphill and three-putting that green. And I missed a bunch of short ones on the front and some birdie opportunities, but it felt awful with the putter. I hit a lot of good shots today, but just couldn’t get the ball to go in the hole.”

Long set up with the winning putt with the 6-iron approach from 175 yards with the ball below his feet in dormant grass on a mound to the right of the fairway.

The 31-year-old former Duke player earned his PGA Tour card with a 13th-place finish last year on the Web.com Tour’s regular-season money list. In five previous PGA Tour starts, he made only one cut — a tie for 63rd in October in the Safeway Open.

Hadwin finished with a 67, losing a three-stroke lead on the back nine.

“It’s golf,” Hadwin said. “I made a bunch of putts all week and then honestly I was kind of battling it a little bit swing-wise, didn’t quite have it like I did the first three days. It just kind of flat-lined on me there in the last few.”

The Canadian had his fourth straight top-six finish in the event. He was second in 2017 after a third-round 59 at La Quinta Country Club and tied for third last year.