A statement released by the Co Down star's management company, International Sports Management, last night confirmed the end of the young golf star's relationship with his former childhood sweetheart.
It said: "Rory McIlroy's long-time relationship with Holly Sweeney came to an amicable end before the Open Championship."
Sources close to McIlroy confirmed last night that McIlroy has formed a close friendship with the 21-year-old Danish tennis star.
The young golfer, who is widely tipped to be the next Tiger Woods, made two visits to Wimbledon to watch tennis following his US Open triumph four weeks ago.
However, he is believed to have met Wozniacki at the World Heavyweight title boxing match between David Haye and Wladimir Klitschko in Hamburg on July 2.
The following day, Wozniacki wrote on her Twitter account: "Fantastic fight! Also met Rory McIlory, who was sitting just behind me:) Really down to earth great guy:)"
McIlroy has previously admitted that he made a mistake when he broke off his relationship with his childhood sweetheart at the start of the season to concentrate on his golf.
She was pictured at his side during homecoming celebrations following his triumphant win at the US Open this summer and has been the subject of much media coverage since his astonishing victory.
"I realised pretty quickly that I had made a mistake, and I had to do a lot of begging and grovelling to get her back," he said at the time. "She is fantastic."
The pair had been going steady since they were teenagers and she was also a shoulder to cry on at Augusta National in April, when McIlroy's management team flew her out for the final day of the Masters.
"She takes my mind off golf... and having her there made Sunday night a lot easier, having someone there you really know," he said in the aftermath of his traumatic loss in Augusta.
The couple lived together with their two dogs at McIlroy's 13-acre Co Down hideaway.
But speculation about his relationship with the young tennis star, labelled "a county club couple made in heaven" in one internet blog site, has been rife since the pair were spotted having an intimate dinner together at a London restaurant earlier this month.
Tongues were also set wagging by their followers on their mutual Twitter sites with a flirty exchange of tweets, including a cheeky birthday greeting McIlroy sent the tennis player on her 21st birthday last Monday, in which he tweeted: "You're getting old."
She replied: "At least now you will be able to buy me a drink in the US" and "Not only in Hamburg", a few hours later.
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