Luke Donald recovered from a faltering start to remain one shot clear after The Heritage third round on Saturday, staying on track to become world number one for the first time.
Briton Donald, who will take over at the top of the rankings if he triumphs at Harbour Town Golf Links on Sunday, fired a one-under-par 70 for an 11-under total of 202.
Jim Furyk, who won last year’s title in a playoff, was second after carding a 69, one shot in front of fellow American Scott Verplank (67) and Zimbabwe’s Brendon de Jonge (66).
Englishman Donald, a stroke ahead overnight, double-bogeyed the par-five second after hitting his tee shot out of bounds but fought back on a blustery afternoon to retain control of the PGA Tour event.
The world number three mixed three birdies with a bogey to reach the turn in level-par 36 and picked up one more shot at the par-four 16th, where he struck a superb approach to three feet and knocked in the putt.
“It was tougher today, the wind was more of a factor and the greens are getting firmer and crustier,” Donald told reporters. “And I was pleased with bringing it back after that slow start.”
Asked about his strategy for Sunday’s final round, he replied: “It’s pretty bunched behind me ... so with just a one-shot lead you can’t play protective golf.
“You have to go out there and try to win it, make some birdies and not try to hold on to that lead. I don’t know if it’s going to be windy again tomorrow, but the course is only getting harder and faster.”
Furyk had been tied for the lead with Donald playing the last but his second shot bounced over the green into a bunker from where he failed to get up and down to avoid a bogey.
“I’m pleased with my round,” said Furyk after recording four birdies and two bogeys on a firm and fast-running Harbour Town layout.
“I knew the greens were going to get baked out and the golf course was going to be a lot tougher. Getting it in under par today was the goal and putting myself in a good spot for tomorrow.
“When I’m playing well, I feel like this golf course suits my game. I look at the leaderboard - Luke Donald, Scott Verplank - those are guys who I think have very similar style games to me. And I’m sure they’re confident as well.”
Donald, who claimed his maiden PGA Tour victory at the WGC-Accenture Match Play Championship in February, is bidding to become the fourth world number one in less than six months.
He will leapfrog top-ranked Martin Kaymer, who is not playing this week, and number two Lee Westwood even if the latter wins the Indonesian Masters because the Heritage carries more ranking points than the Asian Tour event.
“Obviously we’re a long way apart right now in terms of where we are (playing), but we never wish bad on each other,” Donald said of Westwood, with whom he has exchanged friendly banter this week via Twitter.
“I have an opportunity to go out there and win, and if I do, then I know what’s going to happen.”
Westwood, deposed as number one by German Kaymer earlier this year, can regain the top spot with a victory in Indonesia if Donald fails to win at Hilton Head.
He was five shots clear after Saturday’s third round in the Asian Tour event at the Royale Jakarta Golf Club.