Rory McIlroy completed golf's career Grand Slam with a tearful Masters victory on Sunday, sinking a tense four-foot birdie putt on the first hole of a sudden death playoff to defeat Justin Rose.

World number two McIlroy snapped an 11-year major win drought despite squandering the lead three times in the final round, weeping as he finally captured the green jacket that so long eluded him.

"It feels incredible," McIlroy said. "This is my 17th time here. I was wondering if it would ever be my time. I'm thrilled and so proud to be able to call myself a Masters champion."

McIlroy joined Jack Nicklaus, Tiger Woods, Gary Player, Gene Sarazen and Ben Hogan as the only players to win all four majors.

Needing a par on the 72nd hole to win, McIlroy plunked his approach at the par-4 18th into a greenside bunker, blasted out to five feet but then missed a tension-packed par putt for history, the ball going left of the hole as the crowd groaned.

That set up the playoff at the 18th, which Rose had birdied from 20 feet in regulation.

Rose dropped his approach 15 feet from the hole but McIlroy then landed his second shot four feet from the pin.

Tension built as Rose missed right of the hole and tapped in for par, leaving McIlroy a second chance to win and make history.

This time, McIlroy's stroke was true and the emotions exploded after 10 prior failed attempts to complete a career Slam at Augusta National.

As the crowd roared, McIlroy grabbed his head, sank to his knees and put his head down on the 18th green and began crying.

"There was a lot of pent up emotion that came out on that 18th green," McIlroy said. "It's a moment like that that makes all the close calls worth it."

McIlroy recalled when he led in 2011 seeking his first major at age 21 only to collapse on the back nine at shoot 80.

"I would say it was 14 years in the making going out from 2011 and feeling I could have done something there."

McIlroy hugged caddie Harry Diamond, put his head down and hands on his knees and wept again. He stepped off the green and hugged his wife and daughter, again crying as emotions poured out while the crowd chanted his name.

As he greeted friends with a smile, McIlroy excused himself, saying, "I've got to go get a green jacket."

The 35-year-old from Northern Ireland endured a nightmare start, back-nine collapse and the 72nd-hole bogey to secure his fifth career major title in epic fashion with an iconic day-long fightback for the ages.

McIlroy, who had not won a major since the 2014 PGA Championship, fired a one-over par 73 in the final round to finish 72 holes on 11-under 277 alongside Rose, who shot a closing 66 with birdies on six of the last eight holes.

What had looked for much of the day like a McIlroy march to the green jacket instead became a intense dogfight.

A knife's edge

The Masters hung on a knife's edge with Rose and McIlroy level at 10-under when McIlroy landed his second shot at the par-five 15th six feet from the hole. McIlroy missed the eagle putt but his tap-in birdie was enough to regain the lead.

Rose replied with a his birdie at 18 but with history on the line, McIlroy blasted his approach at the par-four 17th to two feet and tapped in for birdie to reclaim the lead again, only to lose it once more.

In addition to the champion's green jacket, McIlroy received a record $4.2 million winner's prize from a record $21 million purse.

McIlroy took his third title of the year after The Players Championship and the Pebble Beach Pro-Am, giving him 29 career US PGA Tour triumphs.

The troubles started early for McIlroy although his playing partner, Bryson DeChambeau, had faded from the scene by the finish.

McIlroy started with a double bogey to share the lead with DeChambeau, who birdied the second for the lead.

But McIlroy benefitted from two-shot swings on the next two holes to suddenly have a three-shot lead and a birdie at the ninth left him four in front at the turn.