John Huh claimed a dramatic victory at the Mayakoba Golf Classic after a marathon eight-hole play-off with Robert Allenby.
Huh had posted an eagle and six birdies en route to a final-round eight-under-par 63 and was two shots behind leader Allenby on 13-under overall when he signed his scorecard.
But the Australian double-bogeyed his final hole after driving into the trees to let the American back in.
The two couldn't be separated and went blow-for-blow in the play-off until Allenby finally cracked at the eighth extra hole when he found a hazard and couldn't save par.
That allowed the 21-year-old Huh to tap in for his first career PGA Tour victory and settle the second-longest play-off in PGA Tour history.
"It's amazing," said Huh, who began the day seven shot off the lead. "It's my rookie year, especially, and playing in my fifth event on the PGA Tour. I just couldn't put it in words. It's amazing, I can't believe it happened right now.
"I was nervous, especially when you're playing out there against Robert Allenby. I was trying to calm myself down, but it was hard."
For Allenby, it is now 11 years since he last won on the PGA Tour.
"Obviously, disappointed, disappointed that I didn't like hit 3-wood off 18 in regulation, like I should have," said the veteran Australian. "But that's the way it goes. You make some mistakes sometimes, and that was a major one, obviously.
"I mean, I had this tournament in the bag, a two-shot lead with one hole to play and just played it like a rookie, pretty much.
"I played so awesome all day. I mean, I did nothing wrong all day. I played great. I putted great. I hit the ball great. I did everything that I needed to do coming down the stretch and then to give it away at 18 is very, very disappointing."
Matt Every and Colt Knost both signed for 66 to tie for third, two strokes off the lead, while Chris Stroud was a stroke behind entering the final hole, but also made a double bogey for a 71.
It dropped him into a tie for fifth at 10 under with third-round leader Daniel Summerhays, Dicky Pride and Alejandro Canizares.
Summerhays closed with a disappointing 73, while Pride and Canizares shot 66.