Xander Schauffele was the beneficiary of an 18th-hole double-bogey from leader Sahith Theegala, going on to win the Travelers Championship by two strokes with a birdie at the last.
Schauffele finished the tournament at 19 under with rounds of 63, 63, 67 and finally a 68 on Sunday as wind picked up and the scoring conditions worsened.
The win is the sixth of his PGA Tour career and his first singles win since January 2019, also collecting the Zurich Classic of New Orleans in a team format with Patrick Cantlay in April of this season.
It was Theegala controlling the final stages after he moved to 19 under and the outright lead with birdies at 13, 15 and 17 down the stretch, but after finding the fairway bunker on 18, he muffed his first attempt to get out, requiring another two shots to get to the green, before his bogey putt lipped out.
It meant Schauffele only needed par to claim the championship, and he went one better, finishing in style with a perfect drive, approach and putt for birdie.
Speaking on the 18th green after his winning putt, he said it felt incredible to convert a 54-hole lead for the first time in his career.
"It's incredible," Schauffele said. "I was looking at birdie just to get into a play-off and saw there was a bit of a hiccup with Sahith when I was standing on the tee.
"I knew I had to hit that fairway and hit it anywhere on the green to make par."
Theegala finished tied for second at 17 under along with J.T. Poston, who was one of three players to shoot 64 or better on Sunday (also Chesson Hadley and Scott Stallings).
In outright fourth was Michael Thorbjornsen following a week he will never forget, finishing at 15 under after being the only amateur to make the cut, closing his week with rounds of 65, 66 and 66 to make a statement about his future on the PGA Tour.
Hadley held outright fifth place at 14 under, going bogey-free with four birdies and an eagle for his 64, while Keith Mitchell and Kevin Kisner shared sixth place at 12 under, with Kisner carding a disappointing 71 on Sunday to take himself out of contention.
The round of the day came from Stallings, who went bogey-free with seven birdies for his 63, rounding out the top 10 in a tie for eighth along with Brian Harman, Chez Reavie, William McGirt and Nick Hardy.
A star-studded group finished tied for 13th at 10 under, featuring world number one Scottie Scheffler, number six Cantlay and fellow top-20 American Tony Finau. It was tough work for the stars, with an even par 70 for Scheffler on Sunday, while Cantlay entered the day one stroke off the lead and carded a 76.
Rory McIlroy and recent winner Lee Kyoung-hoon were in the group that completed out the top 20.