Danny Willett shot a superb five-under-par 67 to take advantage of Jordan Spieth’s capitulation and win the Masters after a thrilling final round.
The Englishman claimed his maiden major by three shots to become the first Briton to win the Masters for 20 years.
Defending champion and overnight leader Spieth, 22, led by five shots as he approached the 10th at Augusta, but then dropped six shots in three holes.
The American ended with a one-over 73, tying for second with Lee Westwood.
Westwood, another Englishman, carded a three-under 69 on the final day to earn his second Masters runners-up finish.
But Spieth will be left ruing a remarkable collapse on the iconic par-three 12th, twice finding the water in front of the green to eventually score a quadruple bogey.
That catapulted Willett, 28, into the outright lead – one that he would not relinquish after signing for the joint-lowest round of the final day.
Relive all the drama at Augusta
The world number 12, playing three groups ahead of Spieth, received a standing ovation as he walked towards the 18th green, on the verge of emulating fellow Englishman Nick Faldo in 1996.
Spieth was also given a sympathetic reception as he trudged towards the clubhouse about 30 minutes later, but it was no consolation for the emotional two-time major winner.
And the world number two faced further ignominy by having to help Willett into the Green Jacket.
“It’s been crazy. You can’t really describe the emotions and feelings,” said Willett. “We all try to play good golf and someone has to win and fortunately today it was my day.
“It was a very surreal day when you look back at the ebbs and flows.”
Green Jacket seals Willett’s rapid rise
Willett is one of the golf’s rising stars having climbed from outside the top 100 to the fringe of the top 10 in less than two years.
But few would have predicted a first major win in only his second appearance on the unforgiving Augusta course.
Especially because, until last week, the Yorkshireman’s participation at the Masters had been in doubt – with his wife Nicole due to give birth on the final day.
However, the early arrival of baby Zachariah meant Willett, who said he would stay at home if his son had not been born, was able to play.
Opening rounds of 70, 74 and 72 gave Willett a fighting chance, three behind Spieth going into Sunday.
He moved just a stroke behind Spieth with a birdie at the eighth, his eagle putt just coming up short, on his way to a front-nine 34.
However, Willett could not have imagined what drama was going to unfold on the back nine.
Spieth’s remarkable meltdown opens the door
Spieth, aiming to become only the fourth back-to-back winner at Augusta, looked set to continue his Masters dominance with a clinical display on the front nine.
He stood on the 10th tee with a comfortable five-shot lead after four straight birdies, only to see that advantage dwindle to one by the time the Texan walked onto the 12th.
Bogeys at the 11th and 12th, coupled with birdies for Willett just ahead on the 13th and 14th, enabled a four-shot swing.
Then came the remarkable meltdown from Spieth at the 12th.
His career has been characterised by steel, calm and composure, making the meltdown even more remarkable.
The world number two planted his tee shot into the water in front of the green, clubbed a heavy second attempt into Rae’s Creek, finally finding the bunker at the back for five.
He managed to get up and down from there – but the damage was already done.
Willett, seemingly oblivious to all the drama behind him, took the outright lead as a result of Spieth’s triple bogey.
“It was just a lack of discipline coming off the two bogeys instead of realising I was still leading the Masters by a couple of shots,” Spieth said.
“I have no doubt about my ability to close majors, I just think it was a very tough 30 minutes that hopefully I don’t experience again.”
English invasion of Augusta
While Willett rightly takes all the plaudits, he was not the only Englishman to impress in the final round.
Westwood, who also finished second in 2010, moved into contention with three birdies before the turn.
Chipping in for an eagle on the par-five 15th put the 44-year-old former world number one within a shot of Willett, only for a bogey on the next and two final pars leaving him short.
Former Ryder Cup player Paul Casey and young Yorkshireman Matt Fitzpatrick, the only two men in the 57-man field to match Willett’s final-round 67, finished tied fourth and tied seventh respectively.
Justin Rose, the 2013 US Open champion, finished in a tie for 10th on one over, alongside Northern Ireland’s four-time major winner Rory McIlroy.
More to follow.