Rory McIlroy is officially a free agent and can sign on the dotted line for a $250m deal with equipment giant, Nike.

MIlroy and Acushnet Co., which has supplied the 23-year-old Northern Ireland star with Titleist and FootJoy gear respectively, since he turned pro in September 2007, has released the World No. 1 from their relationship after this year.

The announcement allows McIlroy to pursue a lucrative endorsement contract, with strong indications that he will sign with Nike in a deal that one industry observer estimated at $20 million a year.

It will provide Nike with golf’s two biggest stars in McIlroy and Tiger Woods.

This is the second time in the last 10 years that Acushnet, which has an history of fiscal prudence, has not stood in the way of a No. 1 player going after big money. Woods, who had an equipment deal with Titleist when he turned pro, left for the Nike golf ball in 2000 and then the Nike golf clubs in 2002.

Phil Mickelson won his first Masters with Titleist in 2004, and the Fairhaven, Mass., company let him out of his contract later that summer to sign a lucrative deal with Callaway.

“Our goal has been to provide Rory with the best equipment and service that would help him be the best player he could possibly be,” Acushnet chief executive Wally Uihlein said in a statement.

“Rory has been a great ambassador for the Titleist and FootJoy brands, and in turn, we are proud of how our equipment has contributed to his success. We wish Rory all the best, both personally and professionally, going forward.”

McIlroy, who defeated Woods in an 18-hole exhibition in China on Monday, thanked the Acushnet staff for ‘five very exciting and successful years.’

“I will always appreciate the contribution Titleist has made in helping me become the player I am today,” McIlroy said.

Not since Woods has a player had this much potential at such a young age. McIlroy was 19 when he won the Dubai Desert Classic for his first win as a pro, and he followed that with a 62 in the final round to win at Quail Hollow for his first PGA Tour win.

McIlroy shattered US Open scoring records at Congressional last summer to win by eight shots and when he won his second major at Kiawah Island, he became the youngest player since Ballesteros in 1980 with two majors. Only five players have won majors by at least eight shots since 1976 — three by Woods, two by McIlroy.

They have become friends in recent months. They were in the same group five times during the FedEx Cup playoffs, and the conversation came easily.

That led to the 18-hole exhibition on Monday, the first time Woods has agreed to a head-to-head match since the old ‘Battle at Bighorn’ days against Sergio Garcia.

McIlroy won the encounter by a shot.

But before they had teed off there was Nike banners and balloons everywhere and McIlroy was seen arriving at the China course wearing a pair of Nike trainers.

Then on the fourth hole,  McIlroy even took one of Woods’ Nike clubs and took a few practice swings.

However Nike are refusing to confirm the new sporting arrangement.

“We are declining comment on rumours and speculation,” Nike spokeswoman Beth Gast said.

McIlroy is not playing the HSBC Champions this week in China and will end his year starting the following week with the Singapore Open, the Hong Kong Open and the DP World Tour Championship in Dubai.

He would have two months until his next tournament in Abu Dhabi, giving him time to test new equipment.

Even as McIlroy was getting courted by other companies, Titleist did not put up a big fight. The company has a history of putting the brand before the player, as it did with Woods, Mickelson, David Duval after he reached No. 1 in the world and Sergio Garcia. It prides itself on having the most tour players use its golf ball, though it also has some 80 players around the world under contract to use its golf balls and golf clubs.

This year might have been particularly costly, however, especially with incentive clauses in the contracts. It had six players from the top 16 in the world as full staff players — McIlroy, Adam Scott, US Open champion Webb Simpson, Jason Dufner, Steve Stricker and Nick Watney.

* Thanks to Irish Examiner for this story and a paper that I contribute regularly.