LONDON (AP) - U.S. Open champion Rory McIlroy split from agent Chubby Chandler on Friday to link up with Ryder Cup partner Graeme McDowell at Dublin-based management company Horizon.

The 22-year-old Northern Irishman had been represented by Chandler's International Sports Management since turning professional in 2007.

"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," McIlroy said in a statement. "Therefore I am delighted to be joining Horizon and I look forward to working with my new team."

ISM said it took "great pride ... in guiding him successfully through his formative years as a professional golfer."

"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," the third-ranked McIlroy said. "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."