Dustin Johnson, seeking a win that would put him back atop the world rankings going into next week's US Open, fired a five-under par 65 on Saturday to share the FedEx St. Jude Classic lead with Andrew Putnam.
Johnson, who took a one-shot lead into Saturday's third round at TPC Southwind in Memphis, had six birdies and one bogey in his five-under effort to join Putnam atop the leaderboard on 15-under 195.
Putnam had six birdies without a bogey in his 64, capping his round with a 17-foot birdie putt at the 18th.
The leaders were five strokes in front of Stewart Cink, whose six-under par 64 was highlighted by a hole-in-one at the par-three eighth.
Cink, the 2009 British Open champion, also had five birdies, rolling in a 29-footer at the 14th before his only bogey of the day at 17.
Johnson, who lost the world number one ranking to Justin Thomas last month after reigning for 64 straight weeks, can move back atop the summit with a win on Sunday.
He birdied two of his first five holes before his only bogey of the day at the ninth, where he was in the rough off the tee.
His four birdies coming in included a birdie at the par-five 16th, where his shot out of a greenside bunker left him five feet to the hole.
That gave him a one-shot edge over fellow American Putnam, who grabbed his share of the lead with his long birdie putt at the last, capping a superb day on the greens.
"It's going to feel a little different than the typical Sunday round of golf," said Putnam, who will be playing in the final group on Sunday for the first time.
Johnson has 17 PGA Tour victories, including the 2016 US Open, while Putnam's 43 career starts have yielded nothing higher than a top-five finish.
"I'm excited for it," Putnam said of the challenge. "I've earned my way here and I feel like it's going to be a fun day."