Rory McIlroy can match Jack Nicklaus’ haul of 18 major but Pádraig Harrington has warned the new Open champion that he must strike while the iron is hot and take advantage of his best years.
With Tiger Woods in decline and no-one else in the game capable of beating McIlroy’s A game, the Holywood superstar will need to rack up the majors at the current rate of three every four years to have a chance of catching Jack.
But given the quality of his A game and the experience he is gaining in leaps and bounds, Harrington still expects McIlroy to go on now and dominate golf.
Massively impressed by the 25 year old’s recent development, Harrington said: “Age is on his side but not necessarily time.
“I do see a change coming quickly in golf with Rory driving the ball probably better than anybody else in the game.
"There are a couple of guys longer than him but he is more effective - he hits it straighter and higher.
"So he has an advantage and he does live off that advantage because the courses and conditions suit him.
"If he putts okay, he's going to be right there. But with the kids coming out of college now, in five to 10 years’ time there are going to be a lot of players like that.”
Believing few plays will be able to live with McIlroy’s A game for the next few years, Harrington added: “At the moment when he plays well, he has stolen a march on everybody else.
“Whoever it is, if Rory’s got his A game, whoever is trying to beat him is going to need their A game to be there with him.
“It doesn’t matter it that’s an Adam Scott or Tiger. They are going to have to play their very best to compete with him.
“At the moment he has the ability to go into the next number of majors as the favourite for a long number of years. But in time — and Tiger looked invincible for such a long time — the kids in college now are going to learn from Rory and come out with similar games.
“They might not be as good as him but they will have similarities. There will be more players like him.
“Rory is pretty comfortable that if he plays his A game, he can win and it’s a nice way to be because there are very few people who can compete with his A game at the moment.
“But time appears to have caught up with Tiger Woods and we just wouldn’t have foreseen that a few years ago.
“A few years ago, nobody would have ever have thought that Tiger would have stopped at 14. When he got to 14 it was thought it was inevitable he would get to 18.
“So if Rory is to get to high numbers [in major wins], it is the next number of years that will determine it. The more years where he wins two or three majors — remember Tiger had four in 12 calendar months — that’s how you get to 14.
“Time is on his side but in ten years’ time, his rate might slow down to one every two years.
“You are looking for somebody like an Adam Scott or a Henrik Stenson to have the game to compete with Rory’s A game. Or maybe Jason Day if he starts winning in majors because he has the physical side of the game.”
McIlroy’s power and his fearlessness with the driver is still his biggest weapon.
But Harrington warned: "Tiger had that advantage and it's been eaten up now. And Rory's advantage will be eaten up in time too.
"He is young and he's got time to win more majors, but the more he wins, the quicker the better.
"There might be three players like him now, in 10 years' time there might be 15.”
With three major wins in four years, McIlroy could win 18 if he maintains that pace for the next 20 years.
But while Harrington points to Woods’ current six-year major drought as a warning, he reckons the most impressive thing about McIlroy’s development recently is than he’s learning about himself all the time.
“As tough as that loss at the  Masters was, he is learning off the golf course and on the golf course,” Harrington said. “He is gaining in experience and confidence all the time.
“The one major he hasn’t won is the major he was made for, which is Augusta.
“They said he couldn’t win on a links but while he got good weather and half the field got the right side of the draw, he took advantage of it. That’s the big difference.
“The hardest thing in golf is definitely winning from the front and Rory is very capable of doing that.”