After his beatdown in the main event of UFC 137 tonight (Oct. 29) at the hands of Nick Diaz, B.J. Penn says that he is retiring from mixed martial arts.

In the post-fight interview with Joe Rogan, Penn kept it short and sweet:

"I've got a daughter. I've got another on the way. I don't want to go home looking like this again. I'm done."

So it would appear that not only did Diaz make the best case possible for a title shot against Georges St. Pierre with his performance inside the Octagon, he also retired one of the greatest fighters that ever lived.

Anyone think Penn is just running on emotion right now and needs some time to think it through before making a huge decision like this? Or have we truly seen the final fight of "The Prodigy's" career?

Sound off, Maniacs.