Tiger Woods clinched his 14th major title by defeating valiant veteran Rocco Mediate at the first sudden-death hole of an absorbing US Open play-off.
Mediate, 45, bogeyed the 1st hole and was three behind Woods at three over after 10, before the world number one bogeyed two holes in succession.
The outsider posted three consecutive birdies to take the lead after 15.
Mediate missed an 18-footer for the title, a Woods birdie took the match on and Mediate's bogey ended a great duel.
At 158 in the world rankings, Mediate was one of the biggest outsiders ever to take part in a major play-off as he tried to become the oldest winner of the championship.
But although he was up against 32-year-old Woods, who has never lost a tournament having led on the final day, there was little to choose between the pair, and the underdog was a fraction away from one of the biggest shocks in sporting history.
Woods had birdied the 18th on Sunday to take the tournament to a play-off and it was another last-hole birdie that denied Mediate, propelling the pair into sudden death.
The victory took Woods one step closer to Jack Nicklaus's record of 18 majors, and was made more remarkable as the Californian struggled with a knee injury over the course of the five-day contest at Torrey Pines.
"This is probably the greatest tournament I've ever had," Woods said afterwards, paying tribute to the estimated 25,000 fans who turned up to watch the extra day's play."
Mediate said: "I would have loved to have won and I don't know what else to say. They wanted a show, they got one."
The atmosphere was fervent from the start and when Mediate nervously prodded a par putt to drop behind at the 1st it seemed as if the occasion may have got to him, but he responded superbly at the dramatic 3rd hole.
His tee shot at the par-three overlooking the ocean trickled inches past the flag and the resulting birdie put him one shot ahead as Woods was unable to save par from a plugged lie in the front bunker.
The shock lead did not last long as Mediate's approach from the sand at the 5th bounced into the wilderness off a cart path, and he did well to just drop the one shot.
Woods appeared to have underlined his supremacy with a drive and a nine iron to four feet at the 500-plus yard par-four 6th, and added another birdie at the next with a 12-foot putt to move two clear.
But he had his problems as well and he dropped a shot at the 8th after finding another perilous spot in the bunker.
Putting opened the gap again, Woods holing two good ones, the second from the apron off the 10th green and Mediate missing two relative tiddlers.
Mediate somehow stayed in contention with some determined play but was unexpectedly aided by Woods finding sand at the next two holes.
With his injured knee causing extreme discomfort, Woods drove so far right at the 15th that he found a bunker on another hole, and Mediate kept up the pressure by finding the middle of the green in regulation.
Woods produced one of the very great shots, drawing one in from the sand to six feet, but Mediate got his blow in first, holing a snaking one from around 20 feet. Woods missed and was one down with only three to play.
He left two birdie chances agonisingly short at the next two holes and Mediate calmly sank a three-footer to take a one-shot advantage to the final hole.
Mediate found the fairway trap and laid up 124 yards short, while Woods sent a three-iron towering over the pond to find the par-five in two.
After Woods two-putted, Mediate, having seen his putt to make history stay up, then had to hole a nerve-jangler from around a yard to keep the contest alive.
The first additional hole was the 7th and, while Woods ripped a monster drive way down the fairway, Mediate found the sand and then had to drop out from the stands beside the green.
With Woods making a solid four, Mediate needed to hole from around 20 feet but this time he could not do it and his great adventure came to an end.