But at least the Dubliner is unconcerned by jet-lag. Quite the reverse – he says he actually quite likes it when he flies from east to west.

“It means that I’m tired at night, I sleep earlier and wake up in the morning quite refreshed,” said Harrington, whose latest globe-trotting stint saw him manage fifth place in the Macau Open and a lowly 60th in the Asian Open in Shanghai.

“When I’m at home I’m generally the opposite, awake at night and tired in the morning. That’s why I play well in the States. I like that jet-lag.”

Harrington is his own man too when it comes to scheduling and intends to keep it that way.

He did not play in the British Masters at the Forest of Arden two weeks ago and, for the second year running, he is giving next week’s Volvo PGA championship at Wentworth a miss.

“I would never follow the pack in anything,” said the world number eight. “If there’s a better way I’m happy to find it, not necessarily do the same as everybody else.

“I’m always looking to find new ways of doing things that might be better. I watch what everybody else does and see what I can learn from them, but I’d also be very quick to change things and try new ideas.

“I do it my own way – and make my own mistakes with that.”

On skipping Wentworth again his explanation is simple. He has never had a top 10 finish there and does not see the point in subjecting himself to that.

It is not a “never again” stance he is taking, though.

“I think I need to bring a different game there. I want to have a lot of confidence in my game to be going there because for some reason I don’t.

“If you look at the guys who play well at Wentworth it’s the same names every year. I hit the ball very high now, which is disastrous around Wentworth, and I struggle on the greens because I don’t hit my putts firm enough.

“I intend to go back and hopefully when I do I have a fresh outlook. At the moment it’s one of those things – why have a knock-back at this time of year?”

Even without Tiger Woods, who won on each of his three visits to St Leon-Rot, there is an impressive line-up of stars trying to take the trophy away from Harrington.

Ernie Els, the world number two, could not play in Hamburg last year because of injury but appears this time, as do former world number one Nick Price, ex-US Open champion Retief Goosen and Australian Adam Scott, winner of the Players’ Championship in Florida in March.

And in European terms, all the usual suspects are present, led by Darren Clarke, Lee Westwood, Paul Casey and Colin Montgomerie.

While Montgomerie is understandably more concerned with family matters at present after the break-up of his marriage, he will be facing the prospect of having to qualify for the British Open at his home course Royal Troon if he drops out of the world top 50 this week.

He enters the tournament 50th.