Moments to remember
Harrington's greatest shot: That's easy - it was the five-wood approach to the par-5 17th hole at Royal Birkdale in the 2008 Open Championship.
This was history in the making. The defending holder of the Claret Jug arrived on the 17th tee leading by two shots with two holes left for play.
Greg Norman had made a run at the title but Harrington would not be denied on that memorable Sunday.
He had 272 yards to go with his second shot, and smashed a five-wood shot to within four feet. Harrington duly holed the putt for eagle and earned the right to enjoy his march of triumph down the 18th as he joined an elite club of back-to-back Open champions.
A year earlier Harrington broke two huge barriers - first, by becoming the first home Irish Open champion since John O'Leary in 1982, and then with a sensational Open Championship victory at Carnoustie, defeating Sergio Garcia in a play-off.
Starting the final round six shots behind Garcia, Harrington refused to buckle despite a tangle with the Barry Burn in the closing stages.
The ones that got away
He might have won the 2002 Open at Muirfield, but went for birdie on the last and took a bogey, finishing one shot out of a play-off won by Ernie Els.
At Winged Foot in the 2006 US Open, Harrington again had a near-miss, bogeying the last three holes, when three pars would have enabled him to beat Australian Geoff Ogilvy.
He has had 29 second places in his career, but could analyse each one and very few of them were missed chances to win.
A Ryder Cup debut at Brookline in 1999 ended in defeat amid chaotic scenes as the USA captain Ben Crenshaw and his players staged a big comeback to defeat Europe.