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Scottie Scheffler birdied four of his last five holes to take a five-shot lead heading into the final round of the Tour Championship.
Collin Morikawa is the only player nine shots behind the world number one, having also finished strongly with three birdies on the last four holes at East Lake for a 67.
Scheffler’s third-round 66 puts him within reach of the $25m (£19m) FedEx Cup prize, having missed out after leading in last year’s season-ending tournament.
Two years ago he was already six shots ahead going into the final round, but was overtaken by Rory McIlroy.
“I feel like I did a lot of things well and played solid, so I’m looking forward to the challenge of trying to finish the tournament tomorrow,” he said.
The best finish came from Sahith Theegala, who moved into third place – four behind Morikawa – with five consecutive birdies to end his round, part of a run of seven birdies and one bogey over his last eight holes en route to a 66.
Theegala recovered from a double bogey on the sixth hole after being assessed a two-shot penalty for feeling he hit the sand of a bunker on his backswing.
“I’m pretty sure I broke the rules, so I’m paying the price, and I feel good about it,” Theegala said.
Xander Schauffelle slipped to fourth with a 16-under-par 71, while Shane Lowry climbed to eighth, three shots back, by matching the low round of the day with a 65.
McIlroy is tied for 10th, 15 shots behind the leader, after adding a 68 to his opening round of 69.
