MEMPHIS, Tenn. -- Andrew Putnam will be playing in the last group on Sunday for the first time, looking for his first PGA Tour victory.
His playing partner will be Dustin Johnson, who has won once this year and needs his 18th career victory to reclaim his spot as the world's top-ranked golfer.
No pressure at all.
"It's going to feel a little different than the typical Sunday round of golf, but I'm excited for it," Putnam said. "I've earned my way here, and I feel like it's going to be a fun day. See what happens."
Putnam matched the best round of his short PGA Tour career Saturday with a 6-under 64 and tied Johnson atop the leaderboard at the St. Jude Classic. Johnson had a 65 to match Putnam at 15-under 195 and said he's in great position going into Sunday.
"I can kind of control my own destiny," Johnson said. "If I go out and play really good golf, probably going to win. If I don't, I'm sure Andrew's going to beat me. He's playing really good right now. It's pretty simple."
A two-time winner on the Web.com Tour, Putnam birdied No. 18 to tie up Johnson once again after a bogey-free round and consecutive 64s. Putnam, who joined the tour in 2015, has had only one bogey through 54 holes.
"I'm happy with everything I've been doing," said Putnam, 29, from Washington.
Stewart Cink, who had a hole-in-one on No. 8, matched his low round of the year with a 64 to get to 10 under.
Ricky Werenski got to 10 under but bogeyed No. 18 to finish with a 68. He was tied with Bryan Wesley (69) at 9 under. Brandt Snedeker (70) was at 7 under.
Johnson and Putnam, a 29-year-old from Washington with a pair of top-10s this year on tour, quickly turned the third round at TPC Southwind into a two-man race.
Playing in the final group, Johnson opened with a birdie after hitting his approach to 6 feet on No. 1. Putnam, a group ahead, birdied three of his first four holes and took the lead to himself briefly at 12 under by rolling in from 31 feet for birdie on No. 5.
A tee shot way left on the par-5 No. 3 cost Johnson a penalty and a drop, making par the best he could do. Johnson tied Putnam with a birdie on No. 5. But the man trying to get back to No. 1 before going to the U.S. Open bogeyed No. 9 after hitting his tee shot into the right rough and two-putting from 14 feet.
"I hit two bad drives on both the par-5s. I just kind of pulled them both," Johnson said. "That was it. Other than that, I'm really swinging my irons well."
Johnson rebounded with a birdie on No. 10, hitting his second from 152 yards to 8 feet and tied Putnam again. Putnam rolled in a 22-footer for birdie on No. 12 to reach 13 under, only to see Johnson sink an 8-footer for birdie on No. 13 to tie him up again.
Looking for a victory before going to Shinnecock Hills, Johnson birdied No. 13. On No. 15, he hit his approach 130 yards to within 4 feet for birdie and birdied the par-5 No. 16 after hitting out of the bunker to 5 feet to become the first to reach 15 under.
Putnam rolled in from 17 feet to wrap up his round with a share of the lead, and Johnson could only settle for a two-putt for par.
Cink, who last won The Open Championship in 2009, missed the cut at both the Players Championship and Memorial last week. He took advantage of the par 3s with two birdies and his hole-in-one to keep close to Johnson and Putnam.
"It can be a little bit of a shock when it happens, and suddenly you find yourself right up there in the mix, and you've got to reset yourself," Cink said of his hole-in-one. "But I did a really good job the rest of the way, and I'm proud of that, and I look forward to tomorrow."
Amateur Braden Thornberry shot a 65 and was tied at 6 under. The junior at Mississippi tied for fourth here last year in his tour debut. ... This event, sponsored by FedEx, becomes the World Golf Championships-FedEx St. Jude Invitational in 2019.