The UFC has found a new opponent for John Moraga.

Moraga, who was initially expected to face Jussier Formiga at the UFC on FOX 13 card in Phoenix on Dec. 13, now meets UFC newcomer Willie Gates, sources told MMAFighting.com on Tuesday. Formiga was forced out of the bout with an injured knee.

Gates (11-4) signs with the UFC fresh off an 83-second TKO victory over Hector Sandoval to earn the Tachi Palace Fights 125-pound title on Nov. 6. Gates has won five in a row in 2014 with five first-round finishes.

Moraga (15-3) scored a second-round submission over Justin Scoggins in his last appearance inside the Octagon, bouncing back to the win column following a loss to John Dodson. A former UFC title challenger, Moraga is 2-1 since losing to flyweight champion Demetrious Johnson in 2013.

Headlined by Junior Dos Santos vs. Stipe Miocic, UFC on FOX 13 takes place at the U.S. Airways Arena in Phoenix, Ariz.