In a strange turn of events, Rory McIlroy announced on Friday that he would be leaving International Sports Management and super-agent Chubby Chandler to join the Dublin-based Horizon Sports Management, home of fellow countryman and friend, Graeme McDowell.

It is interesting in terms of the timing of the split as McIlroy was travelling with Chandler for the past few weeks in China and most recently with fellow ISM clients Darren Clarke and Charl Schwartzel to the PGA Grand Slam of Golf in Bermuda.

If there was anything that could be seen as a sign that the 22-year-old US Open Champion was planning on leaving the agency, it came in August when McIlroy expressed some concerns about how ISM was presenting him.

“We sat down [six weeks ago] and he said he was not happy with his brand, sponsors, website or his public relations image. I thought we were sorting things out to his liking,” Chandler said.

“Even though we had that talk I was shocked. I had no inkling, really. Of course it batters away at your self-confidence when you lose someone like Rory because he is as big as they come.”

Also interesting was the manner in which McIlroy chose to break the news to Chandler and the world, seemingly keeping it a secret from everyone except Horizon. Travelling back from Bermuda and before heading to Istanbul to watch some tennis, McIlroy sat down with Chandler in the JFK Airport lounge to break the news to Chandler.

“He said I’ve decided to move on,” Chandler said. “Disappointed and a bit shocked. I thought we had a better relationship than that, but he had his reasons. He said he wanted to freshen things up a bit. It’s one of those things; he’s a 22-year-old with a very strong head who wants to make his own decisions, and one of his decisions was he didn’t want us to manage him any longer.”

For McIlroy’s part, good on him for doing this professionally and face-to-face. With the move coming as a surprise, McIlroy wasn’t available for comment despite some nagging efforts. He did, however, let out this press release:

“I would like to sincerely thank Andrew ‘Chubby’ Chandler and his team for their guidance, representation, and management over the past four years, since turning pro.

“Chubby and his team have played a very important role in my success to date. I have made great progress under their management and for that I will always be grateful.

“I am now keen to move onto the next stage of my career and I feel this will be facilitated by a fresh view and a new structure around me. Therefore I am delighted to be joining Horizon and I look forward to working with my new team.”

While players switching agencies can be as fluid as switching caddies, when players like Tiger Woods and Rory McIlroy make moves, it turns heads. Interestingly enough, Ernie Els doesn’t quite hold that clout as he left ISM last month without so much as a blip on the radar.

Finishing the season with two major champions, Chandler’s ISM stable is far from in trouble, but with Els, McIlroy and now rumors that Schwartzel may be leaving as well, something may be going awry within ISM.

It is very possible that McDowell had a big part in McIlroy’s move. Easily McIlroy’s best friend on Tour, McDowell left ISM in 2009 because Chandler wasn’t giving him enough attention. Of course, McDowell went on to win the 2010 US Open and Chandler vowed to never let anyone the caliber of McDowell slip through their fingers again, although it appears they have done just that.

As for the other members of ISM, Lee Westwood tweeted at McIlroy saying simply, “bizarre decision!” Chandler added that he believe Clarke, who has known Rory from a young age, “is going to feel a little let down” by McIlroy’s decision.

McIlroy’s person website is down, whether it is due to high volume or changes in appearance is unknown.

Chandler is letting the news roll of his back, but he admits there is some pain in the decision for his company.

“Life goes on and, while there’s hurt, I certainly don’t bear any bitterness towards Rory,” Chandler said. “We all know how good he is for our sport and I’d rather reflect on the four good years we had together.”