Three weeks after drinking out of the Claret Jug to celebrate close friend Jordan Spieth's Open victory, Justin Thomas had a major trophy of his own after his victory in the US PGA Championship.

Thomas carded a closing 68 in a thrilling final round at Quail Hollow to finish eight under par, two shots ahead of Patrick Reed, Louis Oosthuizen and Francesco Molinari.

Rickie Fowler and Hideki Matsuyama shared fifth place on five under with Kevin Kisner, who needed to eagle the 18th to force a play-off but ran up a double bogey, dropping back into a tie for seventh with Graham DeLaet.

Jordan Smith, playing in his first major championship, carded a closing 68 to finish in a tie for ninth with Open runner-up Matt Kuchar, former world number one Jason Day and Chris Stroud.

Fowler and Spieth were among the players to wait beside the 18th green to congratulate Thomas, who became the youngest player to shoot 59 on the PGA Tour on his way to winning back-to-back events in Hawaii in January.

"It's awesome and I think they know I would do the same for them," Thomas said. "It's a cool little friendship we have.

"We obviously all want to win. We want to beat the other person. But if we can't win, we at least want to enjoy it with our friends. I think that we'll all be able to enjoy this together and I know it's going to make them more hungry, just like it did for me, (watching) Jordan at the British."

Thomas began the final round two shots off the lead and had to hole from 14 feet on the first for a bogey after visiting three separate bunkers, with a fortunate birdie on the 10th also proving crucial.

The 24-year-old's hooked drive bounced off the trees and back into the fairway, from where he was almost able to find the green. After chipping to eight feet Thomas saw his birdie putt hang on the edge of the hole for nearly 10 seconds before it eventually dropped in.

"The putt on 10 was funny because it snuck up on the hole," he added. "We read it going back a little back right and it never did. I kind of acted like a child and threw a little tantrum, but then it went in and I didn't look so dumb."

Thomas went on to chip in for birdie on the 13th and produced a brilliant tee shot on the 17th to set up another, which allowed him the luxury of a bogey on the 18th.

He added: "'I hate to admit this but I'm kind of superstitious and weird about the night before, or when I get in contention, about people saying stuff, you know, like, 'Let's go out and get it done tomorrow, let's go do this'.

"(But) I truly felt like I was going to win. I remember my girlfriend was supposed to fly out at about 7.00pm and I was like, 'You need to change your flight to later, because I don't know, I just feel like I don't want you to miss this. I feel like I'm going to get it done."

With Rory McIlroy contemplating a break from the game, the upper echelons of the golfing world are becoming clogged with young talent.