Sam Burns outdueled fellow American Keegan Bradley over the back nine on Sunday to win the Valspar Championship and capture his first US PGA Tour title.

Burns fired a final-round three-under par 68 to finish 72 holes on 17-under 267 and defeat Bradley by three strokes at Innisbrook resort's Copperhead course in Palm Harbor, Florida.

The 24-year-old took his breakthrough victory in his 76th PGA start with his wife, parents and siblings among those there to celebrate with him and caddie Travis Perkins.

"It's just, you work so hard for this moment," Burns said, wiping his eyes.

"To have them all here, they have sacrificed so much for me growing up, it really is a dream coming true."

World number 94 Burns, whose prior PGA career best was third at Riviera in February, had been a leader after 36 and 54 holes in prior events but had never managed a victory until now.

"Those moments in the past, they just test you and you learn a lot from them," Burns said.

"Coming down the back nine, Travis and I just tried to stick to our process. In the past, I got away from that. Today I was focused on that."

Burns finished 15-under for the week on the course's par-5 holes, including three birdies on Sunday.

Bradley, the 135th-ranked winner of the 2011 PGA Championship, missed a chance for his fifth US PGA victory and first since the 2018 BMW Championship.

"I just didn't hit the shots I needed coming down the end, but I'm proud of the way I finished off to come in solo second," Bradley said.

Norway's Viktor Hovland and American Cameron Tringale shared third on 271 with Mexico's Abraham Ancer fifth on 272.

Sam Burns, his back to the camera, hugs his father as he celebrates with his family on the 18th green after winning his first US PGA title at the Valspar Championship
Sam Burns, his back to the camera, hugs his father as he celebrates with his family on the 18th green after winning his first US PGA title at the Valspar Championship GETTY IMAGES NORTH AMERICA / Julio Aguilar

Burns and Bradley were deadlocked for the lead at 17-under with six holes remaining after Bradley curled in a tense six-foot par putt at the 12th.

Bradley plunked his tee shot into the water at the par-3 13th on the way to a double bogey while Burns sank a testy eight-foot par putt to seize a two-stroke lead.

Burns dropped his approach inches from the cup at the par-5 14th and made birdie to reach 18-under and lead by three with four holes to play.

Bradley missed a four-foot par putt at the par-3 15th to stay three adrift after a Burns bogey, then Burns sank an 18-foot birdie putt at the par-4 16th to stretch his lead to four shots, a fist pump his first sign of the emotions within.

A closing bogey kept Burns from matching the 72-hole tournament record of 18-under 266 set by Fiji's Vijay Singh in his 2004 triumph.

Bradley and Burns matched the 54-hole course record to put themselves in Sunday's final pairing and the title chase was basically a two-man fight.

They both opened with birdies while Burns added a five-foot birdie putt at the second to grab the lead alone at 16-under.

Bradley stumbled back with a bogey on the third hole but birdied the par-5 fifth and par-4 sixth, dropping approaches inside four and eight feet respectively, to again share the lead.

Burns, 24, curled in a 26-foot birdie putt at the par-4 seventh but made bogey at the par-3 eighth.

Bradley responded with his third birdie in five holes, sinking a 16-foot putt at the par-4 ninth to grab the lead at 17-under.

At the par-5 11th, Burns was left into trees and Bradley way right but both punched out short of the green and while Bradley saved par, Burns made a 15-foot birdie putt to share the lead again.