Andrew Landry held his nerve at the critical moment to claim a second PGA Tour title at The American Express on Sunday.
The 2018 Texas Open champion birdied the final two holes to salvage a five-under 67 in the fourth round and finish two shots ahead of Abraham Ancer (63) in California.
Landry began the fourth round level in a tie for first with Scottie Scheffler and initially looked set to cruise clear of the chasing pack as his compatriot stumbled through the opening six holes.
Three successive bogeys beginning at the 13th allowed the surging Ancer to erase a six-shot deficit, but Landry resisted the challenge after making par at the 16th.
He converted two excellent tee shots into a pair of birdies to close out the tournament at 24 under.
The win will help to erase Landry's memories of his playoff defeat against Jon Rahm on the Stadium Course at PGA West two years ago.
The 32-year-old told reporters: "I had good swing thoughts coming down the stretch. Just got the job done.
"I mean, I think the biggest shot of the tournament was the one on 17."
Scheffler (70) finished a stroke behind Ancer, while Bud Cauley (65) and Sepp Straka (66) shared a tie for fourth.
Another American, Rickie Fowler, finished in a four-way tie for 10th after following his third-round 70 with a disappointing one-under 71.