AUGUSTA -- A security guard pointed down the left side of the 10th fairway to identify the culprit.

It was a tall pine, which now cast its shadow on the white siding of a cabin about 30 yards off the fairway. Not far away, Masters champion Charl Schwartzel's green-jacket coronation was about to begin.

A little over two hours earlier, Rory McIlroy's tee shot had struck the tree, ricocheting the ball left. It came to rest between two cabins, leading to a triple bogey and precipitating his agonizing descent from heavy Masters favorite to an improbable tie for 15th.

Said the security guard, "What a disaster."

Following the 8-over-par round, McIlroy acknowledged as much.

"You know, I was leading this golf tournament with nine holes to go and I just unraveled," he said. "Hit a bad tee shot on 10 and then never, never really recovered."

At 21 years and 11 months, McIlroy sought to become the second youngest Masters champion after Tiger Woods and advance the onslaught of the game's young guns. Instead, by surrendering a four-stroke lead after three rounds, he joined the list of authors of can't-look-away Masters collapses, names that include Greg Norman, Ed Sneed and Ken Venturi, who gave away third-round leads of six, five and four strokes, respectively.

"I don't know what happened because he was going along fine on the front nine," second-place finisher Adam Scott said. "He's a [heck] of a player, and he just needs to let it get out of his system and reset everything and get on with it."

After making three bogeys in his first 54 holes, McIlroy began leaking early Sunday. He bogeyed two of his first five holes and made the turn in 1 over par, but still held the lead at 11 under. At 10, he hooked his tee shot and hit the pine. He punched out from between the cabins, then missed the green badly on his third shot. His fourth, a chip to the green, hit another tree and bounced away from the green. He made a seven.

"I felt comfortable on that tee shot all week, and for some reason I started it a little left of where I wanted to be, hit that tree, and I don't think anyone's been over there in those cabins before," McIlroy said with a laugh.

He bogeyed 11. Second-guessing his putting lines and speeds, McIlroy four-putted the par-3 12th. On the next hole, the par-5 13th, he sent his tee shot into Rae's Creek bordering the left side of the fairway. He dropped his head into his right arm.

"I'd sort of realized, unless I birdied my way in, I realized I didn't have a chance," he said.

His back nine of 43 was the highest of the final two rounds. Of the 296 rounds played in the tournament, only one was higher than McIlroy's Sunday 80, which matched the second-round 80 he shot at the British Open last year after shooting an opening-round 63.

McIlroy is scheduled to fly to Kuala Lumpur this week for the Malaysian Open. A longer flight might not exist.

"I didn't handle it particularly well [Sunday], obviously, but it was a character-building day, put it that way," he said. "I'll come out stronger for it."