GREENSBORO, North Carolina (Reuters) - Webb Simpson won the Wyndham Championship by three strokes on Sunday to capture his first PGA title after two near-misses earlier this season.

The 26-year-old from North Carolina kept his cool to shoot a final-round three-under-par 67 and finish on 18-under at the Sedgefield Country Club.

George McNeil climbed up the leaderboard with a 64 to claim second place and his fellow American Tommy Gainey was a further shot back at 14 under while Fiji's former world number one Vijay Singh was among a group of five players who tied for fourth at 13 under.

Simpson became the 12th first-time winner on the PGA Tour this season but perhaps one of the least surprising after his previous close-shaves.

In March, Simpson finished runner-up by one stroke to Gary Woodland at the Transition Championship in Florida after he made a bogey at the final hole. In May, he was beaten by Bubba Watson in a playoff at the Zurich Classic in New Orleans.

"I never thought that winning on the PGA Tour would be this hard, all the pressure and everything that goes on to win a golf tournament," Simpson said. "But I'm extremely pleased and I really love the way I finished today."

Simpson led by two shots heading into the final round after brilliant finish to his third round on Saturday, where he made four birdies and an eagle in his last six holes.

He did not drop a single shot in a bogey-free round on Sunday and made two late birdies to surge clear and claim the title and go into the FedEx Cup playoffs, starting in New Jersey next week, ranked third overall.

"I've never won so I don't know what it's like playing the week after a win," he said. "I heard it's tough but hopefully I can put this behind me and focus on the golf course next week."

McNeill started the day six shots off the pace and tied for 11th and he admitted he was surprised to finish outright second despite shooting the best score of the final round.

"I thought it (the winning score) was going to be a lot lower," McNeill said.

"(But) I can only control myself. I can't control what everybody else does. I'm very happy with the way I hit it, the way I played, the way I putted."

The tournament marked the last chance for players to climb into the top 125 rankings and qualify for the playoffs and two former major winners snuck in after strong performances.

Ireland's Padraig Harrington, who called off a family holiday to try and qualify, finished at six under par to move from 130th to 124 while South Africa's Ernie Els moved up eight places to 118th after finishing at eight-under.

"You don't know in these playoffs," Els said. "I've got to play good golf though. I played really good the first two days. I'd like to get that back."

But American Justin Leonard was among those who missed out, despite finishing at 10-under. He narrowly missed a 13-foot putt on the 18th that would have got him into the field but ended up ranked 126th.

(Reporting by Julian Linden in New York; Editing by Greg Stutchbury)