How many movies have Iwao Isayama and Sonny Chiba collaborated on?

They have worked on 1 movie together! Their first movie together was G.I. Samurai (1979) and was their highest rated movie together. They have not worked together since G.I. Samurai (1979).

G.I. Samurai (1979)

Crew
Cinematography
Role
Lt. Yoshiaki Iba
Crew
Action Director