The already difficult course did not become easier due to the strong downpour that swept over Oakmont and made life miserable for many of the players. Not least for Sam Burns, who was in sole leadership before the final round but had two double bogeys and six bogeys during the final round.
But the tough weather conditions, which caused the game to be stopped for nearly two hours, also gave great opportunities to climb for those who took the chance. And one who did it was the hidden JJ Spaun.
On the 17th hole, Spaun took over the lead, and then on the last hole, he crowned it all by sinking a masterful putt of 20 meters for birdie.
I never thought I would get to hold this trophy. I have always had dreams and ambitions, but a few months ago I didn't know how good I could be. I'm proud of how hard I've worked, Spaun said.
The victory meant the first major win of his career, as the only player under par, and a prize of around 40 million kronor.
Norwegian third in absence of Swedes
Second came Robert MacIntyre, Scotland, two strokes behind the winner, and third Norwegian Viktor Hovland, who slipped back early after four bogeys on the first nine holes.
I missed some short putts at the beginning and you can't do that if you want to win a major, the 27-year-old said.
No Swedish player managed to make it to the weekend's play, as both Ludvig Åberg and Joakim Lagergren had earlier missed the qualifying limit.