CALIFORNIA (AFP) — Sahith Theegala conjured a back-nine birdie spree to edge into a two-stroke lead after the third round of the PGA Tour's Fortinet Championship in California on Saturday.

Theegala, chasing a first-ever individual title on the tour, carded a five-under-par 67 to put daylight between himself and the pack heading into Sunday's final round.

The bogey-free performance included four birdies in the final seven holes of Silverado Resort's North Course  in Napa, with Theegala moving to 17 under after 54 holes.

That left the 25-year-old from California two clear of three players locked on 15 under including Justin Thomas, Australia's Cam Davis and South Korea's Kim Seong-hyeon.

"My goal hasn't necessarily been to win, but to keep getting better," said Theegala. "Keep putting myself in contention on the back nine come Sunday, and that's what I hope to do tomorrow."

Two-time major champion Thomas vaulted back into contention with a superb seven-under-par 65.