How many movies have Koji Ota and Sonny Chiba collaborated on?

They have worked on 3 movies together! Their first movie together was Invasion of the Neptune Men (1961) while their highest rated movie together was Yakuza Wolf 2: Extend My Condolences (1972). They have not worked together since Yakuza Wolf 2: Extend My Condolences (1972). They are most known for their action films together.