Jim Furyk, who is chasing his 17th USPGA Tour title, fired an even-par 70 in the third round to maintain his lead at the WGC-Bridgestone Invitational.
Furyk reached 11-under 199 and has a one-shot lead over former British Open champion Louis Oosthuizen, who shot a two-under 68 at the Firestone Country Club course.
"I felt like today the golf course played a little bit more difficult, the greens firmed up a little and the wind just made it tough," said Furyk, who has won nine of the 19 times he was the 54-hole leader. "I thought it was tougher to get the ball closer to the pin."
Keegan Bradley shot a 67 and was four shots behind. He will be in the final group Sunday, as tee times were moved ahead because weather forecasters are predicting thunderstorms Sunday morning.
"I'm hoping we don't get a lot of rain and we get to go out and play in the morning and get after it," Furyk said.
Tiger Woods broke par for the first time this week, shooting a two-under 68. Woods, a seven-time winner of this event, however has a lot of ground to make up, as he is 11 shots back.
Woods had 14 pars, three birdies and one bogey in his third round.
"I hit the ball well and made some putts," Woods said. "I just did some work yesterday and found some alignment, some posture things and got my feel back. My blade was releasing properly again, and it felt really comfortable."
Oosthuizen, who won the 2010 Open championship, parred his first seven holes and then made bogey on the par-four eighth. He came right back with a birdie on the ninth.
Oosthuizen, of Mossel Bay, got up and down for birdie on the par-five 16th to get within one. That's where he finished Saturday as he made par on his last two holes.
"I missed a lot of fairways on the front nine, but I hit it a little better on the back nine," Oosthuizen said. "All in all, my short game helped me a lot today. I made some putts to save par."
Rory McIlroy shot a 67 and shares fourth place at minus-six with Steve Stricker, who carded his third-straight 68.
"I hit the ball well from tee to green, and I took a few of my chances early on." McIlroy said.
Justin Rose and Bo Van Pelt both shot four-under 66. They were joined in sixth place at five-under-par 205 by John Senden, who had a 69.
Last year's winner Adam Scott managed a one-over 71 to finish three rounds at two-over-par 212.