Collin Morikawa navigated a crowded field to claim the US PGA Championship on his debut in San Francisco.
The 23-year-old saw off stiff competition from Englishman Paul Casey and American Dustin Johnson to claim his first major.
Bryson DeChambeau, Tony Finau and Jason Day also ran Morikawa close, but the Los Angeles born golfer produced a flawless round to earn the win.
What happened in the final round?
Established Americans Dustin Johnson, Brooks Koepka and Bryson Dechambeau were back to fight it out on the final day, but it was Paul Casey early proceedings with three birdies in the first ten holes.
Dustin Johnson would make a solid, if unspectacular, 2-under charge, while Koepka would fade to a disappointing final round of 74.
But it was youngster Collin Morikawa who produced the best round of golf on Sunday, hitting a 6-under-par 65.
He hit three birdies in his first ten holes, reaching 11 under par by the 14th hole.
The shot of the round came from the 16th tee, Morikawa hitting his first shot within feet of the par four hole.
He required just one more shot, sinking his eagle putt, eventually finishing on 13 under, two clear of Paul Casey and Dustin Johnson.
Who is Collin Morikawa?
Born in Los Angeles, Collin Morikawa attended the University of California in Berkeley, just 20 miles from Harding Park where he claimed his maiden major victory.
As an amateur, Morikawa was the top ranked WAGR golfer.
He turned professional in 2019 and has enjoyed a remarkable start to his career, making 22 consecutive cuts, three behind Tiger Woods’ record of 25.
He won the first PGA event of his career in July 2019 with a three point victory at the Barracuda Championship.
He won his second professional event last month with a playoff victory over Justin Thomas.
-13 C Morikawa (US)
-11 P Casey (Eng), D Johnson (US)
-10 M Wolff, B DeChambeau, T Finau, J Day (Aus)
-9 J Rose (Eng), S Scheffler (US)