Michael Phelps debuted his model girlfriend, Megan Rossee, on the red carpet for the Speedo Athlete Celebration in London last night.

While it may seem like the tall, stunning couple are brand new, sources told The New York Daily News they've been dating since January.

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Not to be outdone, Ryan Lochte also posed with a model of his very own, Annabeth Murphy-Thomas, who also took some time out to pose with another Olympic swimmer, Tyler Clary.

Annabeth wore a custom-made dress fashioned out of excess Speedo Fastskin3 Elite Swimming Suit material.

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Mark Foster, known as one of the most successful British swimmers of all time, also stopped by, as did three-time Olympic gold medalist Nathan Adrian.