Americans Wyndham Clark and Beau Hossler, each seeking a first PGA title, combined for a 10-under par 62 for a one-stroke lead after Saturday's third round of the Zurich Classic.
The US duo thrived in the four-ball (best ball) format at the tour's only pairs event to stand on 26-under 190 after 54 holes at TPC of Louisiana at Avondale.
Clark sank a birdie putt from just inside eight feet at the par-5 18th to lift himself and Hossler ahead of South Korea's Im Sung-jae and American Keith Mitchell, who also fired a 62 in round three.
"We're looking forward to the challenge," Hossler said of the final round. "It's going to be a cool environment and a unique experience frankly to have a chance to win a golf tournament with a partner."
Sharing third on 193 were US duos Nick Hardy and Davis Riley and Matthew NeSmith and Taylor Moore plus Sweden's Vincent Norman and Austrian Matthias Schwab.
Sunday's final round will be played in a foursomes (four-ball) format.
Hossler and Clark, who shot 61 in best ball on Thursday, have known each other since they were 10 but this is their first time paired together.
"Sometimes when you're alone, it feels like you're out on an island. When the momentum gets going bad, when you're on your own, sometimes it's tough to turn that," Clark said.
"With a teammate, you can kind of feed off each other and really not allow that momentum to get going in the wrong direction. I hope tomorrow we're light and loose like we've been all three days."
Clark and Hossler each contributed five birdies for the duo, with Hossler salvaging pars for the pair on the fifth and par-3 14th.
Im birdied six of the first eight holes to lift his duo into the hunt. Mitchell contributed a birdie at the par-5 11th and Im birdied 13 and 16 to keep the pair fighting for the lead to the finish.
"He was honestly incredible," Mitchell said of Im. "The front nine was some of the best golf I've ever seen played ever.
"I could only help him on two holes... but it just didn't matter. He was playing so good. I was high fiving him and watching him roll. All in all, 10-under par, Sung-jae probably could have shot that on his own."
Reigning Olympic champion Xander Schauffele and Patrick Cantlay, the defending champions, shot 66 to share 10th on 196.
Cantlay and Schauffele, ranked fourth and fifth in the world respectively, set a foursomes event record with a 63 on Friday.
American Charley Hoffman aced the 210-yard par-3 ninth hole with a 23-degree hybrid for his third career PGA hole-in-one while Denmark's Nicolai Hojgaard lipped out with his tee shot on the par-4 16th.