According to Page Six, Phelps called it off before the new year and has begun telling friends he's single.
The pair had dated on-and-off for a number of years. Johnson traveled with Phelps to numerous events, including the 2011 FINA World Championships in Shanghai, where Phelps won four gold medals.
Since his record-setting performance at the 2008 Beijing Olympics, Phelps has stayed in the headlines as much for his relationships than his athletic achievements. He's been linked to cocktail waitresses, socialite reality stars and Canadian graduate students. Some of those reports were sketchy, at best, and dubious, at worst.
Phelps recently began training for his Olympic swansong in London. The 26-year-old has repeatedly said the 2012 Summer Games will be his final Olympics. He is expected to try and qualify for seven events for the upcoming Games, one less than swam in Beijing.
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