LOS ANGELES (AFP) — World number four Jon Rahm, chasing his second US PGA Tour title in as many weeks, shares the lead with rookie Davis Thompson heading into the final round of the American Express Tournament.

Fourth-ranked Spaniard Rahm sounded supremely confident after firing an eagle and six birdies on Saturday in a seven-under par 65 to pull level with overnight leader Thompson on 23-under 193 at La Quinta, California.

Thompson, a former amateur standout at the University of Georgia and a winner on the Korn Ferry developmental tour, carded a five-under par 67 to keep himself squarely in the hunt for a first PGA Tour title.

"Nothing but positive. That's all I can say," said former US Open champion Rahm, who won this title in 2018.

"Ball striking felt amazing. Hit a lot of great shots out there off the tee. Giving myself a lot of opportunities with the irons. Took advantage of quite a few of them."