Bryson DeChambeau won the US Open for the second time with the best shot of his life for another memorable finish on the 18th hole at Pinehurst No.2 — and another heavy dose of heartache for Rory McIlroy. 

In a wild final hour of more blunders than brilliance, DeChambeau capped off a week of high entertainment by getting up-and-down from 55 yards out of a bunker, making a 4-foot par putt to close with a 1-over 71.

"That's Payne right there, baby!" DeChambeau screamed as he walked off the 18th green.

Payne Stewart famously made a 15-foot par putt on the final hole in 1999 at the first US Open at Pinehurst No.2, beating Phil Mickelson by one shot. 

DeChambeau says he was inspired to go to SMU when he saw a mural of Stewart on campus.

The par putt wasn't as long or as dramatic as Stewart's in 1999. 

The celebration was. 

DeChambeau repeatedly pumped those strong arms as he screamed to the blue sky, turning in every direction to a gallery that cheered him on all week.

McIlroy was in the scoring room, devastated by another close call in a major.

This one will string. As much as this US Open will be remembered for DeChambeau's marvellous bunker shot, McIlroy played a big part by shockingly missing two short putts, the last one from just inside 4 feet for par on the final hole. He closed with a 69.

He had the look of a winner for so long, running off four birdies in a five-hole stretch around the turn. He was a model of cool, the opposite of DeChambeau's exuberance.

McIlroy was two shots ahead walking to the 14th tee. The chants grew louder — "Ror-EE! Ror-EE!" and DeChambeau could hear them.

McIlroy took bogey from behind the 15th green, but he stayed one ahead when DeChambeau, playing in the group behind him, had his first three-putt of the week on the 15th when he missed from 4 feet.

And that's where this US Open took a devastating turn for McIlroy. He missed a 30-inch par putt on the 16th hole to fall back into a tie. On the 18th hole, McIlroy's tee shot landed behind a notorious wiregrass bush. He blasted out short of the green and pitched beautifully to 4 feet.

And he missed again.

McIlroy was watching from the scoring room as DeChambeau escaped from an awful lie left of the fairway — a tree in his back swing, a root in front of the golf ball — and punched it out into the bunker. He expertly blasted a shot from the soft sand that rolled out on the crispy green to set up the winning putt.

"I still can't believe that up-and-down," DeChambeau said as he watched a replay from the video screen during the trophy presentation. 

"Probably the best shot of my life."

McIlroy spun the tyres of his car in the gravel as he left quickly without comment. Since he won the US Open at Congressional in 2011, he has seven top 10s without a victory — it's been more than 100 years since anyone did that well without going home with the trophy.

DeChambeau becomes the second LIV Golf player to win a major, following Brooks Koepka at the PGA Championship last year.

An image of Stewart's famous pose was on the pin flag at the 18th, and DeChambeau put on a Stewart-inspired flat cap during the trophy presentation, later replacing it with his "Crushers" cap from LIV.

He finished at 6-under 274.

AP