U.S. Open champion Webb Simpson birdied his final two holes Saturday to stay atop the leaderboard after the third round of the Greenbrier Classic.

Simpson, the second-round leader by a stroke, extended his cushion by one thanks to his 5-under 65. He finished 54 holes at 14-under 196 at The Old White TPC.

Simpson vaulted to fifth in the world rankings based on his U.S. Open triumph. No one within four of his lead is in the top 100 in the rankings, making Simpson a heavy favorite on Sunday.

But that doesn't matter to Simpson.

"I've been blessed enough to win three times already," Simpson said in a televised interview. "I don't have to go out and prove anything to anyone, but more than anything, I want to be patient."

Troy Kelly fired an 8-under 62 early Saturday and vaulted into second place at minus-12.

Ken Duke (65), J.B. Holmes (66) and Charlie Beljan (67) share third place at 11-under 199, while Ted Potter, Jr. is alone in sixth after his 6-under 64 took him to minus-10.

With Tiger Woods and Phil Mickelson both missing the cut, the tournament needed some star power at the top of the leaderboard and it got with Simpson, who won his only major at Olympic Club three weeks ago.

After the second round was completed Saturday morning, Simpson plodded along with six straight pars to open his round. At the par-4 seventh, he rolled in an 11-foot birdie putt, which tied him for the lead.

Kelly got into the clubhouse at 12-under par and Simpson didn't gain any ground with five consecutive pars around the turn. Simpson poured in a 7-foot birdie putt at the 13th to get within one, then tied Kelly for first with another 7-foot birdie putt, this time at 14.

Simpson had decent birdie looks at 15 and 16, but couldn't convert. He knocked his second at the par-5 17th into a greenside bunker and blasted out to six feet. The U.S. Open champ drained the birdie putt to grab the lead by himself.

Late Friday, Simpson birdied the par-3 18th to take the lead. On Saturday, he ran home a 20-footer for birdie to extend his margin to two strokes heading into Sunday's final round.

"I knew there were birdie holes coming up on the back," Simpson said in a televised interview. "It's not a big cushion at all. I'm going to go out and try and make birdies."

Simpson's closest contender is Kelly, a relatively unknown player who battled a hip injury in recent years.

On Saturday, Kelly flew out of the gate with four birdies in his first six holes, including one from off the green at the second. Kelly sank a 30-footer for birdie at the par-3 eighth, but he took the lead with a 5-foot birdie putt at the 12th.

Kelly, who played the PGA Tour, rather unsuccessfully, in 2009, made an 11- foot birdie putt at 16, and followed with a short birdie putt at the 17th. He signed for his 62, which was good for first at the time, but is two shy of the lead at the end of play.

He will be looking for his first PGA Tour victory and will try to parlay years of contending on lower tours, including three top-3s on the Nationwide Tour a year ago, into battling the reigning U.S. Open champion in the final pairing on Sunday.

"My time the last couple years out there has been good, and last year I got into contention sometimes and had some success," said Kelly. "So it will be a different stage tomorrow, but I can kind of learn off those, and I think tomorrow will be a good learning experience for me."

Blake Adams (64), Graham DeLaet (64), Charlie Wi (68) and Martin Flores (69) share seventh at 9-under 201.

NOTES: Simpson won twice last year in addition to his U.S. Open title...This is the fourth time he's owned at least a share of the 54-hole lead and he translated one of his previous three leads into victory...Defending champion Scott Stallings shot an even-par 70 on Saturday and is tied for 49th at 3- under par...Tom Watson, the golf pro emeritus at The Old White TPC, struggled to a 1-over 71 and is at 1-under par.