Eli Wallach for the most part had been known as a skilled, respected character actor in films, television & theater for 50+ years. I wouldn't even say he was miscast, as with Sofia and the infamous (gasp) George Hamilton.

It's just that in this GFIII part he went a bit over the top as the old world mafioso trying to pass himself off as the cutesy, charming old man. It's a shame Lee Stasberg was no longer around to have coached him in the part.