Gunthorpe entered the final round tied for the lead at even-par 144, before separating himself on Sunday with the low round of the day.

Jeff Collett of Ottumwa, Iowa, and Kevin VandenBerg of Pulaski, New York, shared runner-up honors at 3-under 213. Collett carded rounds of 73-71-69, while VandenBerg posted 71-73-69, both mounting late charges but falling just short.

Gunthorpe’s closing 68 proved decisive, turning a three-way tie into a one-shot victory and securing his second title in the event, having previously won in 2022.

Chad Branton of Cartersville, Georgia, finished fourth at 2-under 214, while a six-player group tied for fifth at even-par 216, including Mark Sanchez (Kentfield, California), Brendan Hester (Singer Island, Florida), William Carter (Laurinburg, North Carolina), Todd Doss (Mandeville, Louisiana), Trae Cassell (Riverdale, Georgia), and John Wright (Oswego, Illinois).

Defending champion Bryan Hoops of Scottsdale, Arizona, finished T-11 at 2-over 218, while 2024 winner Jon Lindstrom of Denver, Colorado, placed 26th at 6-over 222.

The 62-year-old Gunthorpe, a mechanical contractor who owns an HVAC and plumbing business, is as unconventional as his résumé suggests. A self-taught golfer who has never taken a lesson, he built his swing by studying Jack Nicklaus.

As a kid, Gunthorpe would pore over Nicklaus’ “Golf My Way” series in Golf Digest, cutting out each installment and compiling them into a personal guide.

Later, long before swing analysis became common, he began videotaping his own motion—refining a technique built almost entirely on feel.