Tiger Woods held off a late fightback by fellow American Rocco Mediate and sporadic knee pain to win his 14th major title in a nailbiting play-off for the US Open at Torrey Pines.

The world number one, three shots ahead after 10 holes, slipped to one behind playing the last before triumphing in sudden-death with a regulation par at the 19th hole on the South Course at Torrey Pines.

Woods, who birdied the par-five 18th to match Mediate's level-par round of 71, sealed his third US Open victory with a two-putt par at the seventh where his birdie attempt from 25 feet fell inches short.

Mediate bogeyed the hole after driving into a fairway bunker and pulling his approach into the left rough 100 yards short of the green. After reaching the green in three, he failed to sink the par putt from 20 feet.

"Today was just unreal," a beaming Woods said after joining his childhood idol Jack Nicklaus as the only player to win each of the four majors at least three times.

"It just kept ebbing and flowing, back and forth, back and forth. It was a great battle all day. Three shots on this golf course isn't much and I was kind of slapping it around."

Throughout the tournament Woods had been nursing a painful left knee after having arthroscopic surgery two months ago.

Asked how he felt after playing five days in a row, he replied: "I'm glad I'm done. I'm done. I don't feel like playing any more. The atmosphere is what kept me going. They (the fans) made the tournament."

Mediate, who had been bidding to become the oldest US Open champion at 45, was delighted with his recovery after trailing by three shots with eight play-off holes remaining.

"Obviously I would love to have won but it was a great day," said the Florida resident, who was world-ranked a lowly 158th last week.

"Three down after 10, I thought it would be over quick but I just kept hanging around. This is huge for me."

Woods, who had previously won the US Open in 2000 and 2002, appeared to have the 18-hole play-off in his grasp after forging two strokes up at the turn.

Watched by huge galleries and a media contingent of around 100, Mediate missed a 10-footer to bogey the 10th, where Woods parred after ramming in an 18-footer, and trail by three before the drama heightened on the closing stretch.

However, Woods then bogeyed the next two holes for his lead to be cut to one, finding a bunker off the tee at the par-three 11th and driving into a fairway bunker at the par-four 12th.

After matching birdies at the par-five 13th, Mediate drew level with Woods with a birdie at the 269-yard par-four 14th. Mediate's drive ended up just short of the green from where he chipped to two feet.

Woods also ended up close to the green with his tee shot but in the right rough. After chipping to eight feet, he lipped out with his birdie putt.

Mediate struck a dagger blow at the par-four 15th, reaching the green in two and sinking a curling 25-footer for birdie. Woods, who had struck a brilliant second shot from a fairway bunker to 12 feet, missed his birdie attempt to drop one behind.

The next two holes were parred before Woods coolly two-putted from long range to birdie the 18th and take the playoff into sudden-death.

Reuters