Brendan Steele birdied two of his last three holes to successfully defend his Safeway Open crown on Sunday.
Steele finished at 15 under at Silverado Country Club to earn his third PGA Tour win by two strokes over Tony Finau.
American Steele shot a final-round three-under 69 to hold off the field in Napa, California.
Finau made an early charge, spurred by an eagle on the par-five fifth hole.
He added two more birdies before making a double bogey on the par-four 14th. Finau made one final push by birdieing the par-five 18th after a monstrous drive.
Fresh off a dominant Presidents Cup victory, Phil Mickelson got the 2017-18 PGA Tour season kicked off with a tied for third with Chesson Hadley at 12 under.
Mickelson had four birdies and one bogey on the back nine of his final-round 70.
Hadley birdied two of his last three holes to join Mickelson at 12 under. He also broke the course record this week with a second-round 11-under 61.