This according to sherdog:

Todd Duffee has pulled out of his heavyweight bout against Paul Buentello at UFC 107 on Dec. 12 in Memphis, Tenn., due to an injury.

“(Withdrawing) was one of the hardest decisions I’ve had to make,” said Duffee, who would not disclose the nature of his injury.

Duffee, 23, burst onto the UFC scene with a record-setting seven-second knockout of Tim Hague at UFC 102 in August. The undefeated heavyweight, who recently relocated to Las Vegas to attend the University of Nevada-Las Vegas, hopes to be back in action by early 2010.

“It was a fight I was really looking forward to,” Buentello told Sherdog.com on Tuesday. “We really matched up well.”

Mike Russow and Stefan Struve have been presented as two potential replacements for Duffee, said Buentello.

 

This is too bad for both the UFC and Duffee.  After his 7 second knockout, a matchup with Buentello seemed like a great way for the UFC to showcase Duffee against a true veteran fighter.  Hopefully he heals fast from whatever is preventing him from fighting.

Source:Duffee out of 107