Jim Furyk recorded par on 16 holes, one birdie and one bogey for an even par round to enter Sunday's fourth round with a one-stroke lead at -11.
Louie Oosthuizen shot a two-under 68 to pull within one shot of Furyk, including a key birdie on the par-5 No. 16.
Due to the expected weather throughout the day Sunday, those two will also be playing with Keegan Bradley, who shot a 3-under 67 and now stands at -7 for the tournament.
Sunday's round will be all threesome pairings from the No. 1 and No. 10 tees starting at 8 a.m. in an effort to get the round completed during the day with the PGA Championship coming up in next week.
Rory McIlroy and Steve Stricker are each at -6 for the tournament, 5 strokes back of Furyk. Stricker bogeyed two of the final three holes Saturday.
No. 1 ranked Luke Donald and Jason Dufner each struggled Saturday, shooting 1 over and 3 over, respectively, and both sit at -4 for the tournament.
Tiger Woods' playing partner, Branden Grace, appeared as though he might challenge the course record after recording birdies on six of the first 10 holes. He ended up carding a 66 and stands at -2. Woods shot -2 for the day and is at even par for the weekend.