Disaster befell Harrington, though, as he zig-zagged his way down the 16th and then sent his fourth shot at the par-five from greenside rough into the pond guarding the front of the green.

A triple-bogey eight was the end result as Woods carded a birdie four on the way to a second consecutive 65 that sealed his 90th victory worldwide, his 70th PGA Tour win, his fifth title of the year and the second in as many weeks after landing last Sunday’s Buick Open.

Harrington had started his final round at 10 under par with a three-stroke lead over the world number one.

Having both parred the opening hole, Woods piled the pressure on Harrington at the par-five second by sinking a 24-foot eagle putt to move to nine under.

Woods also birdied the fourth and Harrington’s three-shot lead had evaporated.

Woods’ putter was as hot as the weather and another birdie on the fifth gave him the lead.

Harrington was not without his chances and at the eighth his 14ft birdie putt came up short by inches, but he handed the advantage to Woods at the ninth with his first significant error of the round.

Woods had hit his second shot to seven feet but Harrington, from the fairway, could only find a greenside bunker.

The Irishman escaped from the sand to inside six feet but Woods holed for birdie to move into a two-shot lead at 12 under.

Harrington clawed a shot back at the 11th and was back on level terms when Woods bogeyed the par-four 13th.

There was more bad news for Woods at the next when he found rough at the back of a greenside bunker with his approach and then pitched his third shot into the sand.

Harrington sank his par putt from 14 feet, celebrating with a fist pump while Woods chipped to five feet and took his bogey to fall to 10 under.

Both men parred the 15th but the tables dramatically turned back in Woods’ favour at the par-five 16th.

The duo missed the fairway off the tee, Harrington to the right and Woods to the left.

The world number one laid up in the fairway but the Irishman found a mound of rough at the front edge of a fairway bunker and sent his next shot through the green.

By that time Woods had produced some magic from 182 yards, his eight-iron approach stopping a foot from the hole.

There was more woe for Harrington as his wedge out of the rough hopped onto the green and bounced into the water, leading to a triple-bogey eight.

Woods’ birdie gave him a three-shot lead with two to play and he sealed the win in style with another birdie on the last.

Harrington posted a 72 to fall into a tie for second with Australia’s Robert Allenby, who shot a 66 to finish at eight under.

Hunter Mahan and Masters champion Angel Cabrera finished on seven under in a tie for fourth while Open winner Stewart Cink and his fellow American Steve Stricker closed at six under alongside Spaniard Miguel Angel Jimenez.

England’s Lee Westwood closed at five under for ninth place following a 65 that was his best round of the week and secured his fourth consecutive top-10 finish, including a tie for third at The Open.

Oliver Wilson finished 11th at three under with a closing 71 while compatriot Ian Poulter was 15th.

Former tournament winner Darren Clarke, the 2003 champion, shot a 69 to finish level par for the week, tied for 22nd in a group also including Sergio Garcia.