LAS VEGAS — UFC heavyweight champion Cain Velasquez has injured his right knee in training, forcing him out of his title defense against Fabricio Werdum on Nov. 15.
Mark Hunt will meet Werdum for an interim heavyweight title at UFC 180, the mixed martial arts promotion's debut in Mexico.
Velasquez (13-1) was the main focus of the UFC's first card in Mexico City, where the 21,000-seat arena sold out in eight hours.
The Mexican-American champion says he is "unbelievably disappointed" by the latest in his series of injuries. Velasquez hasn't fought since October 2013, when he beat Junior Dos Santos in his second title defense.
The 40-year-old Hunt (10-8-1), from New Zealand, beat Roy Nelson on Sept. 20.
Werdum (18-5-1), who is from Brazil, has won seven of his last eight fights.