After Nick Diaz beat him down, Penn was interviewed after the fight with UFC color commentator Joe Rogan.
"I have a daughter and I don't want to go on looking like this," said Penn on the PPV broadcast to Rogan, his left eye swollen completely shut. "I'm done."
Penn was pushed around all fight and wasn't responding to Diaz's punches even though Diaz was left completely open.
The third round came and Diaz pressed again, and it looked like for the first time in his legendary career Penn would be finished. But the heart of the former champion kept him in it, and he proceeded to get battered around.
After the fight BJ's left eye was just a gigantic purple lump, and now his career seems to be over.
Now, whether he will be retiring for good or whether it was just a heat-of-the-moment decision is yet to be known. Penn is only 32 and could have some more fights left.
If Penn worked on his cardio, he could have had this fight. By the middle of the second round he was done, though. Diaz's body shots had taken their toll on Penn and stole the gas and life out of the former UFC lightweight and welterweight champion.
It seems like the UFC and MMA have lost two legends tonight.