MICHAEL PHELPS IS THE MAN! HE DATED BOTH MISS CALIFORNIA'S ON THE DOWN LOW!

Olympian Michael Phelps has a thing for Miss California. Both of them.
Nicole Johnson, who just days ago was crowned Miss California 2010, admitted to TMZ.com that she had a year-long romantic relationship with the gold medalist.

"Now that it is after the fact, I will admit that we were together," she said. "We agreed to keep this private because it was the only thing that he could keep private ... we remain close friends."

But it turns out, according to PerezHilton.com, that Phelps, 24, may have cheated on Johnson with none other than former Miss California and solo-sex tapist Carrie Prejean, 22.

"Nicole Johnson dated Michael Phelps for a year during 2007 -2008," a source tells the site. "The main reason they ended their relationship is because Carrie Prejean started dating Michael… . and bragging about it while he was still with Nicole."

Unfortunately for Johnson, even Prejean's grandma said it's true.

"Carrie and Michael have been out to baseball games and lunch," Jeanette Coppolla told RadarOnline.com in April. "He always calls her when he is in town and they go out."

And apparently, casual Carrie understood Phelps is a ladies man.

"Carrie knows that he has dated a lot of girls but she enjoys going out with him and isn't serious about being in a relationship with him," she said. "He's a nice guy and she likes him."