Padraig Harrington is determined to become golf's equivalent of Count Dracula in the Alfred Dunhill Links Championship and suck the blood out of the Order of Merit title race.

The Open and US PGA champion has had blood tests that confirm that he is physically on the limit after his double Major winning season.

But despite his fatigue and the fact that England's Lee Westwood is breathing down his neck in the race for the European money title, Harrington reckons he can still kill off the opposition at St Andrews, Kingsbarns and Carnoustie before the season-ending Volvo Masters at Valderrama.

He said: "I've got two tournaments left, this and the Volvo Masters.  I think I've got to play really well in one of them in order to win this Order of Merit.  If I can win one of the two events, I think that more or less guarantees me the Order of Merit.

"The Volvo Masters is on a golf course that's real hard work for me but these golf courses aren't.  These really suit me while Valderrama doesn't necessarily suit me.  So it's got to be this week to perform."

Twice a winner of the Alfred Dunhill Links title and Open champion at Carnoustie two years ago, Harrington said: "I would be better off with a break, yes, but I would never not be here.  I'd crawl over to this tournament.  This is one of the most enjoyable tournaments of the year and one of my best opportunities of the year to win.

"I feel fine, even though I know from different things that I am a little bit run down, so the key is obviously not to overdo things this week.  It's a tough week in these conditions."

Harrington revealed that he hasn't been able to do any serious work on his game since his Open win at Royal Birkdale in July in a concerted effort not to overstress his body.

And that's why he's keen to wrap up his second Order of Merit title this week rather than putting himself under pressure in the season-ending Volvo Masters at Valderrama.

His year won't end  in Spain, however, as he is committed to playing 2009 season-opening HSBC Champions Tournament in Shanghai from November 6-9 and the Barclays Singapore Open the following week.

A trip to California for Tiger Woods' end of year Chevron World Challenge is also on the cards though the Dubliner is determined to wrap up his year in early November so that he will avoids a repeat of last winter, when he picked up shingles due to fatigue and overwork.

He's already seen the telltale signs after undergoing blood tests recenty, explaining: "The blood tests show that all of the markers were tired. I was low in anti‑oxidants; my white blood cells were too active and a couple of other indicators basically showed that I'm fatigued.

"Last winter, I got sick twice.  This year, I am fatigued or run down and the key is not to let it go further so that I don't lose a winter.

"The key is that when I finish my season this year, I am ready to do some practice, do some work and get into the gym. I don't want to lose another winter, which is when you can do the main body of your work."

With three Majors in the bag, Harrington is amazed that he now has more Grand Slam titles than Sandy Lyle, Ian Woosnam, Bernhard Langer or Jose Maria Olazabal.

But he only has eyes for the future and believes he still has another eight years to catch his boyhood idols - six-time Major winner Nick Faldo or five-time champion Seve Ballesteros.

Looking ahead, he said: "If I was to catch Seve at five or Nick at six, it's something that I have to get my head around and one of the tasks is to believe it and to go ahead and do it.

"I reckon I have at least another eight years of being competitive, and I think that there's plenty of time to win plenty more majors and the key is to make sure I do believe my game is getting better, and mentally as well."