Rory McIlroy hit the low round of the day to jump to the top of the field after the third round of the WGC-St. Jude Invitational in Memphis on Saturday.
McIlroy finished in style with three successive birdies, coaxing in a 27-foot putt at the last to take the lead with an eight-under-par 62 in ideal conditions at TPC Southwind.
The County Down man moved to 12-under par, one stroke better than American Brooks Koepka, who had a seven-birdie 64.
McIlroy and Koepka will be paired on Sunday, their first time playing together in the final round of a PGA Tour event.
Halfway leader Matthew Fitzpatrick of England slipped two shots off the pace with an inconsistent 69.
Spaniard Jon Rahm, Australian Marc Leishman and Swede Alex Noren are three shots behind, certainly not out of it even though all eyes will be on the two frontrunners.
McIlroy, who missed the cut last week at the Open Championship in his homeland at Royal Portrush, said precise wedge play had been the key to his score on Saturday.
"I had a lot of good (approach yardage) numbers where I could go ahead and make a full committed swing," he told CBS television
"I just dialled my distances in today with the wedges. It worked today. One of my goals was to hit it pin high and I hit it pin high most of the day.
"These greens are so pure if you get it on line and get it rolling properly."
"I've holed a lot of putts this week."