Is this ‘mystery blonde’ Michael Phelps’ new girlfriend?

While Ryan Lochte was making headlines for his bachelorhood and one-night stands, Michael Phelps has quietly been in a relationship with a Los Angeles woman for five months.

According to various sources, including E! Online, the woman pictured below with Phelps and his four gold medals is a 25-year-old cocktail waitress named Megan Rossee. She and the Olympic legend began dating five months ago.

[ Photos: Phelps' new girlfriend Megan Rossee ]

Video of the couple in London has already begun to surface as well.

Phelps managed to keep the relationship quiet through his Olympic swims, having ceded the "do you have a girlfriend" spotlight to teammate Lochte. Considering how high profile he is and how Rossee didn't seem to be keeping the relationship secret (see below), that's an impressive achievement.

Rossee's Twitter timeline shows she was in London last week, though it's unknown whether she attended Phelps' races. The only thing a look through wire photos showed was that she wasn't sitting near Phelps' family if she did.

She sent a message to Phelps early in the week: "This probably will get lost in your tweets but since i cant text i miss you and cant wait to spend time with you for real xo."

How sweet! She could have sent him a private message and told him the same thing, but chose to do it in public instead! Another thing she chose to do in public: Post a picture of herself pushing a baby stroller and joking about how she might be doing that in five or 10 years.

Michael and Megan made their public debut at a red carpet event on Monday night.

Related Michael Phelps video on Yahoo! Sports:

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