The Horse Race (1974) Part 1

Episode 9. In exchange for a condemned human's freedom, Virdon agrees to ride a chimpanzee prefect's horse in a match race, only to learn his opponent is Urko. Virdon decides to take part in the dangerous race even though he runs the risk of being captured by Urko. Of course, Urko blatantly cheats in order to make certain his winning streak remains intact. 

to be continued...