It seems to me that he basically played himself in Rocky V. I doubt he was smart enough to actually act much.
so true
Rocky V was really awful though, the street fight at the end between Rocky and Tommy “the machine” Gunn was a joke. You had a similiar situation 15 years later in Rocky VI where Antonio Tarver’s character (Mason “the line” Dixon) was basically a fictional version of himself, since Tarver is a real-life obscure boxer. But that film was far better because it was more about Rocky’s struggles with his own life, instead of with his opponent in the ring.