This guy is supposed to be a legit boxer. I think this quote is dated from around 1998. Doesn't sound like any movie is modeled after this one tho.
There's a fighter in Los Angeles named Baez, a welterweight, who wears a tutu to every bout. A traditional pink tutu, usually, like a ballerina's, though he's also got a black and white tutu that he sometimes wears for variety. This Baez is a uniformly dreadful fighter, but he's fast enough to dance away from his opponent for three or four rounds, hooting at the crowd, pointing at his tutu. In the fifth or sixth round, invariably, Baez gets pummeled, though his handlers always try to make sure none of his own blood gets on his tutu. Baez is on cable at least once a month; he is what passes these days for a charismatic boxer.