William Mouw wins ISCO Championship 2025 at Hurstbourne Country Club

• William Mouw secured his first PGA Tour victory at the ISCO Championship.
• Mouw shot a final round 61 to finish at 10 under, one stroke ahead of Paul Peterson.
• The 24-year-old Californian turned pro in 2023 after playing collegiately at Pepperdine.

William Mouw won the ISCO Championship on Sunday at Hurstbourne Country Club, holding off a host of challengers for his first career PGA Tour victory.

Mouw posted a 9-under 61 in the final round to finish 10 under overall. He topped Paul Peterson — who began the day atop the leaderboard at 8 under — by one shot. Peterson was 2 over through nine holes Sunday before making a back-nine charge, with birdies on 10, 14 and 16. But a birdie bid slid past the hole on the par-3 17th, and he was unable to convert a lengthy birdie putt just off the 18th green to force a sudden-death playoff.

A 24-year-old from California, Mouw played collegiately at Pepperdine and turned pro in 2023. This week was his 20th PGA Tour start. Prior to Sunday, his best finish on the circuit was a tie for sixth at the Puerto Rico Open in March.

Mouw’s bogey-free 61 was his best-ever round on the PGA Tour. It equaled the best score of the week (Chan Kim’s also tallied a 61 in Thursday’s first round). And perhaps most impressively, it was the best final-round score in the event’s history, surpassing 62s by Robert Garrigus (2016) and Brett Drewitt (2017). Those scores were at a different time, and a different place, in the tournament’s annals: Garrigus and Drewitt 62s were at the Robert Trent Jones Golf Trail’s Grand National course in Opelika, Alabama, when the event was known as the Barbasol Championship.

This story will be updated.

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