He managed to close with a final round of 71 to finish on 14-under-par 274, two shots ahead of Retief Goosen and Tjaart van der Walt, who finished in joint second at 12-under.
Beginning the day with a comfortable four-shot lead at 13-under, the big man from Northern Ireland would slowly lose his lead during the course of the afternoon, culminating with an exciting finish on the last hole of the day.
Coming down the fairway of the par-5 18th, it appeared Clarke had the tournament wrapped up. He had managed to hold onto a three-shot lead over Goosen during an up-and-down round, which saw several players come in and out of contention for brief periods throughout the day.
After a safe lay-up in the fairway, he had only a sand wedge left into the green. Yet, the ball lay on a downhill lie, and Clarke proceeded to hit it short and into a lake which guards the green.
In the meantime, Goosen, playing with Clarke, had reached the putting surface in two and was looking at a certain birdie.
It appeared there very well might be a two or three shot swing, and quite possibly a playoff.
As it turned out, however, Goosen could do no better than a three-putt for par, while Clarke, after dropping and hitting his fifth to about ten feet, stepped up and canned the testy putt for bogey, to lose just a single shot.
'That was probably the best six I've ever made,' he said following the dramatics. 'It definitely wasn't what I had in mind. My lay-up finished on a down slope and I knew the wedge approach was going to come out low. But it came out lower than I expected.'
Nevertheless, a win is a win, and Clarke will take it just the same. It comes as his first since the Compass Group English Open in June of last year. He celebrated the title with his customary cigar in mouth.
Defending champion and friend of Clarke, Lee Westwood, finished with a rather disappointing final round of 74 to end at 2-under for the tournament. Likewise, American Bruce Vaughan, who held the 18- and the 36-hole lead, fell apart on the weekend, shooting 74-73.
But for aging South African veteran Nick Price, the week produced a pleasant surprise of superb golf, as he took a share of fourth with Titch Moore and Bradford Vaughan at 9-under-par 279.