The CareerBuilder Challenge is Jason Dufner's to lose after a strong eight-under 64 round three performance at La Quinta, California on Saturday.
Dufner birdied seven of the final nine holes of the round to take a two-stroke lead over Jamie Lovemark into the final round on Sunday.
The American's day did not get off to the best start, as he bogeyed his first hole - playing the back nine first - but he recovered well to birdie three of the next four.
He hit another bogey for his sixth, but a near-flawless back half puts world 120-ranked golfer in a commanding position heading into round four at 23-under 193 after two rounds.
Dufner, 38, is chasing a fourth PGA Tour win.
"This is the way you want to play," Dufner told reporters at the completion of his round.
"This is what we work to do. My mindset's at a point where, no matter what happens out there, good swings, bad swings, I know that I can shoot good scores."
Lovemark put in a solid performance himself, as he carded a bogey-free seven-under 65, but it was not enough as he lost ground on Dufner in the lead.
Saturday's best rounds came from Swede David Lingmerth and American Kevin Na, who both carded 10-under 62 to move into fourth and equal-fifth respectively.
Lingmerth struck an eagle on the fourth hole and scored five consecutive birdies on holes 14-18, but he will need to repeat the feat on Sunday to have any hope of catching Dufner, who sits five strokes ahead.
Na shares fifth spot with four other golfers, as Ryan Palmer, Andrew Loupe, John Huh and Phil Mickelson all sit on 17-under 199 after three rounds.
Canadian Adam Hadwin sits in third after matching Dufner's score for the round.