Rasmus Neergaard-Petersen sank a 10-foot pressure putt at the last to edge major winner Cameron Smith and win a maiden DP World Tour title at the Australian Open on Sunday, also sealing a place at the Masters.
It capped a breakthrough year for the 26-year-old Dane, who booked promotion to the PGA Tour next year by finishing third at the DP World Tour Championship in Dubai last month.
He mixed four birdies with three bogeys in his 70 to be 15-under for the tournament, one clear of Australian LIV Golf star Smith (69) and two ahead of South Korea's Kim Si-woo (70).
South Africa's Michael Hollick was fourth, three behind, with Australia's Adam Scott fifth, a shot further back.
Rory McIlroy finished eight off the pace.
"It's hard, I'm really at a loss for words," said Neergaard-Petersen, whose previous European Tour best was second at the Qatar Masters this year.
He repeated the feat on his PGA Tour debut at the Puerto Rico Open while playing on an invite to reinforce his burgeoning credentials.
"On the outside you can look calm but it was a storm inside all day today," he said.
"But I managed to just keep battling and then to get it up and down from there to make that putt on the last, I don't know what to say to be honest."
SEE-SAWING DAY
Neergaard-Petersen took a two-shot lead into the final day at Royal Melbourne, but that was wiped out within the first four holes.
Smith and Kim both nailed early birdies, then a bogey at the fourth by the Dane set up a three-way tie.
A superb approach shot next to the pin at the sixth earned him a tap-in birdie to restore a one-shot lead.
But the Dane lost his nerve with back-to-back bogeys at nine and 10 as Smith kept his cool, draining a three-metre putt on the tricky 10th for the outright lead.
In a see-sawing day, Smith then bogeyed 12th while Neergaard-Petersen slid in a birdie and they headed to the 18th all square.
Neergaard-Petersen sent his approach into long grass at the side of the bunker but recovered to set up a difficult putt for par, which he nailed.
Smith fluffed a five-footer, which would have sent it to a playoff.
Drawcard McIlroy started nine adrift and got the huge crowd fired up with birdies at two and three.
But an anticipated charge unravelled with bogeys at seven, nine and 10 before a grandstand finish saw birdies on the 17th and 18th that sent the fans into a frenzy once more.
"I wish I could have been in contention and been coming down the stretch and battling with the boys," said McIlroy.
"But it's been an amazing week and can't thank everyone in Australia enough for the hospitality and the reception."