Taylor Moore won the Valspar Championship, denying Tommy Fleetwood his first PGA Tour title.
Fleetwood, playing in his 112th PGA Tour event, was one shot behind overnight leader Adam Schenk heading into the final round in Florida.
The 32-year-old shot a one-under-par round of 70, but American Moore closed with a four-under-par 67 to finish 10 under and claim his first PGA Tour victory.
Schenk’s 41-foot putt to force a play-off ricocheted off the lip.
He holed his bogey putt to finish one stroke behind Moore, with Jordan Spieth and Tommy Fleetwood tying for third a shot further back.
Moore, making his 46th PGA Tour appearance, waited with bated breath to see if anyone could match his score after taking the clubhouse lead with a fine round that included five birdies and one bogey.
“It still hasn’t hit me,” Moore, 29, told NBC. “I was just in compete mode and just watching the guys finish, maybe in a play-off, maybe not, and it’s so cool.
“It’s so awesome, it’s what I work for and I’m really excited not just for me but for everyone around me. It’s an exciting time.”
Fleetwood, who has finished second on the PGA Tour four times, moved into a tie for first with a birdie on the par-five 11th.
However, a bogey on the 14th hole after taking two shots to get out of a greenside bunker effectively ended his chances of winning at Innisbrook Resort in Palm Harbor.
After each day, American Schenk had either the outright or joint lead, and he went into the final hole on 10 under par.
After an errant drive left the ball near the base of a tree, Schenk produced a superb left-handed shot with his club head inverted to give himself a chance of saving par.
Following a 41-foot approach, his putt carried slightly too much speed as it hit the pin, then the lip, and agonizingly ricocheted away.
Spieth was also tied for the lead before hitting the water on the 16th, recovering with a bogey to stay in contention.
However, he missed a birdie chance from six feet on the next hole and three-putted the last when a birdie would have forced a play-off.
Sam Burns, who was attempting to win the event for the third time in a row, finished sixth on five under after a final-round 67.