The Irishman opened with a bogey, made a 30-footer at the third, but fell behind again with another bogey straightaway.

After Harrington sank a 15-footer to take the 10th, Singh chipped in at the next for eagle, but he then three-putted the 12th and 15th to trail by one.

The Dubliner, who has just fallen outside of the world’s top 20, instantly gave the short 16th away, missing a four-foot putt after finding sand off the tee, but after lipping out from 10 feet at the last – he was sure he had made it a foot from the hole – he was relieved when Singh found a bunker at the 17th and could not scramble a par.

Harrington later got the better of world number two Vijay Singh with a par on the first extra hole.

In a day of upsets, the biggest name of them all, Tiger Woods, and defending champion David Toms crashed out as well.

After Woods had lost on the last to fellow American Chad Campbell, up stepped David Howell to defeat Phil Mickelson 3&1 and earn himself a last eight match against Australian Geoff Ogilvy, seeded only 52nd of the 64 players who began the event.

Luke Donald could not make it three Europeans through, however. He was never ahead against third seed Retief Goosen and lost when the South African played a superb bunker shot to three feet on the last for birdie.

Three months after beating Woods head-to-head in Shanghai for the best stroke play victory of his career, Howell was a superb four under par in the windy conditions.

Level with seven holes to play he made a 45-foot birdie putt on the short 12th, Mickelson made a mess of the 14th, going from the trees to the bank of a ditch, and the end came when the left-hander, playing only a few miles from his home, bogeyed the 17th as well.

Key to Howell’s win was his success against Woods in November.

“If you stand up to Tiger it would be strange to be intimidated by anybody else,” said the English golfer, who now has a chance to move into the world’s top 10 for the first time in his career.

“It was a big day for me in China and I am sure part of that has rubbed off on me. I have brought that experience with me.

“I was not nervous today. I have been playing nicely and I guess it’s a measure of where I stand in the word order nowadays. I am a lot more comfortable in this situation.

“It was going to be a big challenge playing Phil in his home town, but if you put the scores on the board then whoever it is has to beat that score. It’s a game of numbers at the end of the day.”

Woods is not used to finishing a tournament on Friday. But it has now happened for the second week running.

The Masters and Open champion, who pulled out of the Nissan Open in Los Angeles after 36 holes because of ’flu, lost when he missed a 12-foot birdie putt after trailing all the way from the fourth hole.

Campbell now meets American Ryder Cup captain Tom Lehman, the 46-year-old Lehman again looking like a man on a mission to qualify for his own team by knocking out defending champion Toms 4&3.

Donald had to save par from bunkers on the first two holes for halves, but could not match Goosen’s two-putt birdie at the next.

Winner of the Target World Challenge in California in December, Donald parred the first eight holes and while the one on the seventh brought him all square, with Goosen firing his second way right, the one on the next handed the lead back to the double US Open champion, who pitched to four feet for birdie.

Amazingly, Love did what Singh had done a day earlier when his opening 330-yard drive ran into the water.

Last year’s runner-up Chris DiMarco was gifted the hole as a result, but Love took the third, sixth and eighth and won 3&2.

Ogilvy had the most amazing victory of the day. He stood four down with four to play to Canadian Mike Weir, but won them all and then eagled the third extra hole with a stunning one-iron to four feet.

Goosen meets American Zach Johnson in the other quarter-final, Johnson beating Colin Montgomerie’s conqueror Shingo Katayama 4&3.