The U.S. Open champion shot 5-under-par 65 in the third round Saturday to take a two-stroke lead into the final round.
Simpson had his second consecutive bogey-free round to reach 14-under on The Greenbrier Resort’s Old White TPC Course.
Troy Kelly was second after 62.
Rookie Charlie Beljan, J.B. Holmes and Ken Duke are three shots off the lead. Beljan had 67, Holmes 66, and Duke 65.
Simpson isn’t disappointed that Tiger Woods isn’t around to challenge him. Woods missed the cut for only the ninth time in his PGA career.
“When he’s not lurking around on Saturdays and Sundays, it makes it a little easier I think for other guys,” Simpson said.
Simpson said he plans to peek at the leaderboard, “but the way I look at it is, I’ve got to go shoot under par (Sunday). And if I don’t, somebody’s going to probably (play) pretty good. I think the golf course is playing in such a way that there’s plenty of birdie opportunities.
“I’ve almost got to imagine that these guys are all going to shoot 4, 5 under. I’ve got to stay aggressive.”
He’ll be pursued today by a pair of players making medical comebacks.
Kelly underwent hip-replacement surgery in September 2010 after being diagnosed with arthritis. Holmes had part of his skull removed in September 2011, four months after he started having vertigo symptoms. He returned to the tour in January.