Harris English maintained his two-shot cushion at the WGC-FedEx St. Jude Invitational leaderboard as Bryson DeChambeau climbed up the leaderboard.
Aided by three birdies during his final six holes, English carded a second successive score of 65 at TPC Southwind to sit at 18 under par.
The four-time winner on the PGA Tour endured a bogey-free round on Saturday, pulling clear in the closing stages having at one stage seen both Abraham Ancer and DeChambeau join him in top spot.
After a four at the par-five 16th, English produced an outstanding approach into the green at the next hole before rolling in a birdie putt, boosting his hopes of a wire-to-wire triumph in the tournament.
However, he is well aware that there is still plenty of work to do yet.
"There's a lot of good players behind me and my goal is just stick to my strategy and execute and whatever happens, happens," English said.
DeChambeau is not too far behind after a stunning 63 that saw him come home in just 30 shots. His seven-under score leaves him tied for second with Australian Cameron Smith, who signed for a 65.
"It was awesome being able to strike it that close to the hole all day," DeChambeau, who missed out on playing at the Tokyo Olympics due to contracting coronavirus, said.
"I didn't feel as comfortable as I would have liked with the swing, but the results were there so I was very pleased with the results. And honestly, if I can do that again tomorrow, I give myself a great chance to win."
Ancer is a further two strokes back following a three-under 67, the same score Scottie Scheffler and Ian Poulter both managed to sit just behind the Mexican on 13 under.
Dustin Johnson may still hold out hope of triumphing, with a round of 65 enough to be one of four players on 11 under par. He is joined by Paul Casey, Will Zalatoris and Louis Oosthuizen.
Defending champion Justin Thomas already faced a battle to retain his crown, and the American was only able to shoot 69 on day three.
At seven under for the event, a repeat of his 2020 triumph appears almost impossible, considering he is so far back and the number of players ahead of him.