Gannon Buhr stood on the 18th tee box in 2015 after begging his mother to drive him to Winthrop to see the United States Disc Golf Championship

He stood on the 18th green on Sunday as the youngest USDGC winner in history and fully established that the future of the sport has arrived.

In a thrilling, dominant and absolutely clutch final round, Buhr — at 17 years old with homework to do — took down his first PDGA Pro Major and added yet another chapter to the illustrious history in Rock Hill, South Carolina.

Gannon Buhr celebrates his USDGC win. Photo: Justin Anderson / PDGA Media

Buhr, a two-time PDGA Junior World Champion, blistered the Winthrop Arena to the tune of 12-under final round to grab a one-stroke win over 20-year-old Finnish phenom Niklas Anttila while heading off a Championship Sunday round with Paul McBeth and Calvin Heimburg.

"I can't believe it," Buhr said. "This is the tournament that I wanted to win the most. I can't believe I had to birdie the last five holes, I didn't even realize that, to barely beat Niklas. He's insanely good. He threw every shot and forced me to execute the exact shot and make these clutch putts."

Buhr started the day with a 70-foot throw-in for birdie on one, added a 49-foot birdie putt on 49 and was 9-under on the round through 10 holes.

But Anttila, the two-time Finnish champion who entered with a one-stroke lead over Heimburg and two over McBeth and Buhr, was just as clutch with an 8-under through 11 holes.

Niklas Anttila finished second in his debut at the USDGC. Photo: Justin Anderson / PDGA Media

Anttila's lead grew to three stokes after a double bogey from Buhr on 13 and it was a two-player, whose ages combined to 37, race the rest of the way.

Buhr hit a 60-footer on 14 as Anttila had his first blemish of the round with a bogey for a two-stroke swing. Buhr, the reigning PDGA Rookie of the Year, birdied 16 and took a one-stroke lead into the daunting 18th with another 60-foot putt on 17.

As they had the entire day, both executed 18 to perfection with Buhr tapping in for the win and to enter the USDGC and PDGA Major history books.

Buhr becomes the fourth player to win a Junior and MPO PDGA Major, joining Nate Doss, Nate Sexton and Ricky Wysocki, according to StatMando.