Michael Thompson and Richy Werenski moved two strokes clear atop the leaderboard following the third round of the 3M Open.
Thompson and Werenski extended their joint lead after both golfers carded three-under-par 68s in Minnesota on Saturday.
The American pair shared a one-shot advantage heading into the penultimate round at TPC Twin Cities, where Thompson and Werenski remain the men to beat.
Thompson had four birdies and just one bogey on day three having earlier boasted a four-stroke cushion, while Werenski carded five birdies and a pair of bogeys to also end the round 15 under through 54 holes.
South Africa's Charl Schwartzel (66) and American Tony Finau (69) are the nearest challengers – two shots adrift – ahead of Sunday's final round.
Max Homa climbed 19 positions into outright fifth at 12 under following his seven-under-par 64, while Cameron Tringale (63), Denny McCarthy (64), Alex Noren (66), Harris English (67), Ryan Moore (67), Nick Watney (68) and Cameron Davis (69) are all tied for sixth position.
Defending champion Matthew Wolff is five strokes behind leaders Thompson and Werenski after a difficult round.
After back-to-back rounds in the 60s, Wolff shot a one-under-par 70 to slide seven places into a share of 13th spot, alongside Charles Howell III (67), Emiliano Grillo (64), Adam Long (63), Taylor Gooch (72) and Zhang Xinjun (71).