Webb Simpson produced a second-round 63 on Friday to move within one shot of the lead at the Wyndham Championship.

Jimmy Walker leads on 12 under at Sedgefield Country Club after an eight-under-par 62, but the US Open champion is lurking ominously one shot back.

South African Tim Clark (67), Spaniard Sergio Garcia (63), Sweden's Carl Pettersson (68) and Harris English (64) share third place on 10 under, while Matt Every (66) and Bud Cauley (65) are one shot adrift in a tie for seventh.

Tim Herron matched the tournament record with a 61, but was still seven strokes back.

Walker's 12 under total was one of the best two-day scores in event history. The American produced eight birdies on the day in a bogey-free round.

"I was playing with J.B. (Holmes), and he was bombing the driver everywhere, and I was just kind of bunting the 5-wood around and hitting good approach shots," Walker said.

"It was pretty boring-looking golf -- not a lot of drivers, not a lot of 3-woods. There's a lot of 5-woods and some irons, and it's just kind of placement around the golf course."

Simpson got hot on the back nine with birdies on four of his final five holes to leap into contention.

"To play a round on a golf course this tricky without a bogey is always a good thing," Simpson said.

Overnight leader Pettersson couldn't quite follow up his 62 on day one, with two bogeys in a three-hole span halting his progress midway through his round.

"I struggled today," Pettersson said. "Didn't have much today, but I thought it was a good comeback. ... Two-under par was OK for the game that I had, and hopefully I can hit the ball better on the weekend and have a chance."

Golf 365