Tiger Woods forced an 18-hole play-off with fellow American Rocco Mediate for the US Open title on the final hole of the fourth round at Torrey Pines.
High drama on the 18th saw both Woods and England's Lee Westwood with tricky putts to join Mediate on one under but after Westwood missed the first, the world number one sunk his with his customary coolness.
Both men will return on Monday (1730 BST) to battle it out over a full round, though Woods will go into the day's play as heavy favourite.
With Mediate holding a one-stroke lead and watching from a scoring booth, Woods holed a 15-foot birdie putt on 18 to take the championship into an extra day.
"Unbelievable, I knew he would make it," Mediate said after Woods' putt wrapped around the cup before dropping.
Mediate shot an even-par 71 to finish at a one-under-par 283, while Woods, a little off colour for much of the fourth round as he clearly struggled with an injury, played his first two holes in three over and signed for a 73.
Woods entered Sunday at three under and with a one-stroke lead over Westwood.
But he never got in a consistent rhythm, carding his worst round of the week.
Westwood had a chance for a birdie on 18 as well, but missed from 25 feet and finished a stroke out of the play-off alone in third on an even-par 284.
On his thrilling last-hole putt, Woods said: "That's actually one of the worst parts of the green, it's so bumpy down there. "I told myself it was two-and-a-half balls outside to the right, but make sure you stay committed to it.
"And I did. I hit it good. It took forever to break, but it finally snuck in there at the end."
Woods moved into contention with a 68 on Friday shooting a back nine 30 that included five birdies. He also shot a 70 on Saturday that featured an improbable chip in for birdie from the rough on 17 and a closing eagle at 18.
His dramatic finish on in the fourth round puts Woods in a play-off at a major for the third time.
He beat Bob May at the PGA Championship at Valhalla in 2000 and Chris DiMarco at The Masters in 2005.
Mediate had a putting chance for a two-stroke lead but missed a birdie at the 17th from about 10 feet.
He had another chance at the last from 35 feet, but had to settle for par and wait for the final group to finish.
"I was trying to beat him on my putt, my 35-footer," Mediate said. "I just didn't quite get it out there. But anyway, I made good putts on 16 and 17 just to be here. What can you do?"
Not much more than he did on Sunday.
Mediate was two strokes better than Woods for the day and has only one over par round this week, a 72 on Saturday.
He mentioned on Saturday his desire to get a chance to play with Woods in the final group and ultimately got his wish.
"Sometimes you got to be careful what you wish for," Mediate said. "I knew he would make that putt, that's what he does. I can't believe I'm even in this situation at all. It's great."
But looking back, it is the world number one who is lucky to be still playing.
He started with a double bogey - again -
and played his first two holes in three over as he battled with both his swing and his dodgy left knee for the rest of the day.
He got back to one under with a birdie at the ninth and had the lead after a birdie at the par-three 11th.
But he made a mess of the par-five 13th, recording a bogey there and dropped another shot at 15 to fall to even-par.
"I don't know what it is, but even though I got off to three over through two, I was telling myself that if I got back to even-par for the day, that should win the championship," Woods said. "There were plenty of holes to play, I've done it before, there's no reason I can't do it today. That would have been the winning number. But, I'm also very fortunate to get in a play-off as well."
Like Woods, Westwood also found a bunker - on the opposite side of the fairway - with his drive on the 18th and had to lay up.
He left himself a chance from 20 feet but may have really missed out with a stretch of loose golf earlier on the back nine.
Westwood was two under and in the lead after a birdie at the ninth but he gave a shot right back at the next hole.
He then had consecutive bogeys at numbers 12 and 13 to drop to 1-over but battled back by birdying the 14th, before falling a few feet short when a place in today's play-off was in his grasp.
"It's sickening not to be in the play-off tomorrow," Westwood said.
"While I'm disappointed, I'm pleased with myself and I think that I've proved to myself and a few others that I think there is a major championship in me."
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