Shane Carwin was scheduled to compete on January 1 against Roy Nelson in the co-main event of UFC 125.

"I am going to pull out of the fight with Roy Nelson," Carwin wrote on his website. "I had an MRI yesterday and I have some damage that may really require surgery. "If the doctors do not have to perform surgery then I will be out 8-12 weeks. If they do have to perform surgery I do not know how long I will be out of action."

Carwin is 12-1 and his last fight was a submission loss to Brock Lesnar, who just lost his UFC championship. There has been no announcement on who or if there will be a replacement for Carwin on the card. Now the event is headlined only by a fight with Frankie Edgar and Gray Maynard.

It'd be interesting to see of Lesnar fills that void to get the sour taste out of his mouth from his loss against Cain Velasquez.