Rory McIlroy is one-shot off the lead after the third round at the Tour Championship in Atlanta, in the race for the $15 million first prize.
Brooks Koepka sits atop the leaderboard after a deft chip at the par-five 18th set a up a tap-in birdie and a two-under-par 68 at East Lake.
At 15 under par, Koepka will head into the final round with the narrowest of leads over fellow American Xander Schauffele (67) and McIlroy (68).
McIlroy bounced back from dropped shots on the 13th and 14th with birdies on the 15th and 18th.
Koepka and McIlroy, both four-times major champions, will be paired again, four weeks after locking horns at the WGC-St. Jude Invitational, where Koepka demolished his rival.
McIlroy said it was not particularly important to be in the final pairing, though he still relished the challenge.
"I've been trying not to look at the leaderboards at all this week because it really doesn't matter what anyone else is doing," he said.
He also observed that it had been important to adapt quickly to the significantly cooler conditions on Sunday.
"I think this is the first time ever I've played East Lake and haven't been sweating.
"The ball's not travelling quite as far. Because of the cold air the ball's getting hit by the wind a little more."
Schauffele, meanwhile, had his first ever hole-in-one, from 240 yards no less, at the par-three ninth, where his ball landed on the front of the green and trickled into the cup at perfect pace.
"I told my caddie I think (the first ace) will come in a tournament round and be in a hole longer than 230 (yards). I guess it came true," said the 2017 Tour Championship winner.
"I didn't even see it go in. I looked away. I did pull it too. I'm not going to lie. I yanked it."
The third round was completed on Sunday morning after being suspended on Saturday afternoon due to a thunderstorm.
Six spectators were subsequently injured after a lightning bolt struck a tree on the course.
Five were taken to hospital and all have now been released, the PGA Tour said in a statement
