Mountain Ox is the secondary antagonist of Disney's 1967 live action film The Adventures of Bullwhip Griffin.
In San Francisco, Mountain Ox tries to pick a fight with Bullwhip Griffin. Luckily, Griffin has a nugget of gold in one of his gloves and knows Mountain Ox out with that. This "demonstration of strength" quickly has the town calling him "Bullwhip Griffin" after a comic book/dime novel/folktale-type character of similar strength and guts. Bullwhip Griffin has now become a legend in San Francisco.
Meanwhile, Arabella has come to San Francisco in search of Bullwhip Griffin and her brother and has become a dancer at a local saloon. When Bullwhip Griffin and Jack discover this, the saloon owner recognizes Bullwhip Griffin as the guy who beat up Mountain Ox. He decides to arrange a fight between Bullwhip Griffin and Mountain Ox and have people place bets on it. Of course, he’s unaware of how Bullwhip Griffin beat Mountain Ox in the first place.
So, Arabella, Jack, and Mr. Bartlett try to train Bullwhip Griffin into becoming a fighter, but they know he cannot win by skill. The only possible way is to tire out Mountain Ox by having him run around a lot, and that is pretty much how the fight goes: Bullwhip Griffin eventually wins in a way that I'm not entirely sure is legal by basically tiring out Mountain Ox and having him beat himself.