Just days after he was awarded the new UFC featherweight title by Dana White, Jose Aldo has been forced to pull out of his scheduled UFC 125 title defense against Josh Grispi due to an undisclosed injury.

Heavy MMA first reported the news on Tuesday afternoon, and MMA Fighting has confirmed it with sources.

Aldo (18-1), the final WEC featherweight champion, most recently defeated Manny Gamburyan in September. He captured the 145-pound title in November 2009 when he defeated Mike Brown via second round TKO.

Grispi (14-1) was supposed to fight Erik Koch at WEC 52 earlier this month, but was pulled from that fight card following the announcement of the UFC-WEC merger in October.

No word on which bout will replace Aldo-Grispi as the UFC 125 co-main event.

UFC 125 is scheduled for Jan. 1 in Las Vegas. The event, which will air live on pay-per-view, will be headlined by Frankie Edgar vs. Gray Maynard for the UFC lightweight title.