Brandt Snedeker and Beau Hossler both shot five-under-par 67 to join JJ Spaun and Dylan Frittelli atop the leaderboard, after the third round of the Valero Texas Open on Saturday.
Spaun and Frittelli bogeyed the last par-five 18th hole to finish on 10-under-par after 54 holes, shooting rounds of 69 and 70 respectively on Saturday.
It would have been a five-way tie for the lead had Scott Stallings not also bogeyed the final hole, finding the rough and then the far-side bunker on his second and third shots.
Among the many in the field who have yet to qualify for the US Masters, Matt Kuchar is two strokes back from the leaders on eight-under-par after three rounds.
In what is essentially the final qualifier for the first major of the year, and having missed the cut at Augusta last year, Kuchar is aware of the stakes.
"I think quality play trumps anything," he said.
"I'd take execution over course knowledge any day of the week. I think it's going to take just quality golf tomorrow to win this thing."
After shooting a bogey-free round on Friday, second round leader Ryan Palmer tumbled down the leaderboard on Saturday with a five-over-par 77, finishing in 21st on five-under-par.
Spaun and Hossler are both looking for their first PGA Tour win, while Frittelli last won in 2019 at the John Deere Classic and Snedeker took the Wyndham Championship in 2018.
Hossler finished with momentum on Saturday, making three consecutive birdies from the 14th hole. His career-best finish was a second at the Houston Open in 2018.
A win for Snedeker would make for his 13th trip to Augusta.