It has since become acknowledged as arguably the greatest double-bogey by the winner of a Major championship.
On Carnoustie's treacherous 18th hole, there were two visits to the ubiquitous Barry Burn before the prospective champion secured an unlikely play-off place with a glorious up-and-down from 49 yards.
In gaining an Open champion, Ireland also found a role model who has gone on to have a wonderful influence on shaping the future of the game of golf in this country.
Thoughts of Harrington bring virtues such as decency and integrity immediately to mind. And it seemed highly appropriate on that fateful Sunday in 2007, to see a gifted youngster from Holywood, Co Down, waiting in the wings to receive his medal as Leading Amateur.