AUGUSTA, Ga. - This was to be Rory McIlroy's coronation.

This was to be the official welcoming of the unofficial ring leader of the "Next Best" generation, and this was supposed to be his moment.

He had a four-shot lead at the Masters. On Sunday. And while the guys chasing him weren't regulars at your Saturday low-ball, the names behind McIlroy's on the leader board fluxuated from familiar to almost unknown.

This was going to be McIlroy's "it" win, the one that transformed the 21-year-old, freckle-faced kid from Northern Ireland from a great talent into great player.

Then Sunday happened. Masters Sunday - with the pressure and the focus and the grind and the stakes - happened. Sunday at Augusta National does not give a lot of credence to "supposed to" and "should have." So when McIlroy started to crack from the start - he pulled an easy wedge that led a bogey on No. 1 - the pressure only increased.

A mind-numbing 80 was the final total, and nothing could change that McIlroy went from having at least a share of the lead after each of the first three rounds, to finishing tied for 15th this morning. He was up four on the field when Sunday started. When it was over, he had earned one of the invitations to next year's Masters by finishing among the top-16 and ties. Barely.

"I think it's a Sunday at major, what it can do," McIlroy said. "This is my first experience at it, and hopefully next time I'm in this position I'll be able to handle it a little better. It was a character-building day, put it that way. I'll come out stronger for it."

Three days of excellence were erased in three holes, and any and all chances he had were gone before the sunlight faded on a glorious Georgia afternoon. When the pine straw finally had settled, McIlroy had lost any semblance of control and the leaderboard looked as chaotic as McIlroy's game.

Seven others put their fingers on the tournament lead after McIlroy lost his grip. So complete and one-sided was McIlroy's collapse that he went from leader to underdog to sympathetic figure in the span of the first three holes of the back nine. Such is golf, where one missed swing can mean so much. A rocky start gave way to some doubt, which gave way to disaster on the par-4 10th.

McIlroy hooked his tee shot right into the pine trees and the carom left him between two cabins far off the fairway. He punched out, pulled his third shot left of the green, banged a chip off a tree, pitched up and two-putted for seven.

"I'm very disappointed, you know," he said afterward. "I was leading the golf tournament with nine holes to go, and I just unraveled. I hit a bad tee shot on 10 and then never, never really recovered."

Recovering and rebounding from this experience will be the measure of McIlroy the golfer for the foreseeable future. This likely will be either the fire that forges his championship nerve or the professional footnote that could forever haunt his career accomplishments.

His previous experience leading a major came after a sizzling first round at last year's British Open with a 63 at St. Andrews. McIlroy's second round was a catastrophic 80, blamed more on the weather than his shortcomings, but it looks eerily familiar in round numbers and perspective.

Be it barometric pressure or internal pressure, the questions about McIlroy having talent to win majors have been answered - he shot a final round 62 at Quail Hollow last year and led with nine holes to go Sunday. Whether he has the mental toughness to win majors, however, is another debate for the next time golf's best put tees in the ground.

That's what major championship Sundays do - they announce arrival or they reveal weakness. And sometimes some of both.

"He's such a good player, he's going to win a major sometime," eventual Masters champ Charl Schwartzel said. "Golf is a really funny game - one moment you're on top of it, the next it bites you."

The teeth of that bite is experience, and in golf, it's a cruel and punishing teacher. McIlroy may be talented beyond his years, but he looked every bit 21 on Sunday afternoon. Now he wears the harsh marks of learning golf's most painful lessons on arguably sports' grandest stage.

There's no accelerating experience - only earning it and enduring it. McIlroy's moment of a lifetime teetered on the line between dream come true and career-long scar, and how this pain is remember will be decided by McIlroy in the days, months and tournaments to come.

Before Sunday started, three-time Masters champ Gary Player picked McIlroy to win and said, "it's the ingredients of the person that win major championships. You never know how many times opportunity will knock, and you have to grab it."

The moment grabbed McIlroy, shook him by his floppy-hair and left him spent and disappointed Sunday.

"I'll get over it," McIlroy said. "I've got to look at the positives, and the positive is I led this tournament for 63 holes.

"You know I'll have plenty more chances. I know that. It's very disappointing. Hopefully, it'll build a little bit of character in me, as well."