Langer fired a 66 and Simpson a 67 in the second round at the Crosswater Golf Club in Bend, Ore.

Fred Funk (66), Mike Goodes (67) and Jay Haas (68) were tied for third at 9-under 135. Tom Watson shot a 64, setting the course record, to hold sixth place at 136.

Langer lost a bid for sole possession of the lead with bogeys on two of the last three holes. Simpson birdied 15 and 17.

"I have hit the ball incredibly well over the last two days," Simpson said. "I don't think I've missed but three greens all week and two of the three were on the fringe. I missed 11 today and that led to bogey."