Australian Adam Scott, desperate to win his first PGA Tour title of the year, eagled the par-five 15th on his way to a three-stroke lead in the Tour Championship third round on Saturday.
Joint pacesetter overnight with American Joe Durant, Scott fired a three-under-par 67 to finish at seven-under 203 on a chilly autumnal day at East Lake Golf Club.
The 26-year-old, who has produced seven top-four finishes in 18 Tour starts this season, struck a superb approach to within two feet of the flag at the 495-yard 15th. His tap-in eagle put him one ahead of playing partner Durant for the second time during the round and he stretched further ahead when the American dropped shots on 16 and 17.
Durant, winner of the Walt Disney Classic two weeks ago, had to settle for a share of second place with 2002 champion Vijay Singh after four birdies and four bogeys en route to a 70.
Singh began the day five off the pace before charging up the leaderboard by shooting a best-of-the-week 65. The Fijian world number five covered the back nine in a blistering five-under 30 after reeling off four consecutive birdies from the 12th.
"I played pretty decent, just hanging around the front nine and then got it going on the back nine," Singh told reporters. "I hit some really good shots and made some nice putts. I got a new driver this week and started to drive the ball pretty well."
World number two Jim Furyk birdied three of the last four holes for a 67 to share fourth place at three under with 2004 winner Retief Goosen (68). Tour rookie Trevor Immelman of South Africa (69) and American Tom Pernice junior (67) were a further stroke back in a tie for sixth.
The season-ending Tour Championship brings together the top 30 money winners on the PGA Tour, although world number one Tiger Woods, third-ranked Phil Mickelson and Canada's Stephen Ames are absent from this year's event