Big John McCarthy to Return to the Octagon for UFC on Versus 2 From MMA Fighting: Famed mixed martial arts referee "Big" John McCarthy will return to the UFC's octagon for the first time since 2007 when he oversees action during the upcoming UFC on Versus 2 show. McCarthy's wife Elaine confirmed to MMA Fighting that he has been assigned by the California State Athletic Commission to officiate matches at the event, which takes place on Sunday at the San Diego Sports Arena in San Diego, Calif.