Could this guy play Rocky? - no, I don't think he could.
Rocky was written as a white man (most Italian-Americans being white). There's another scene in Rocky (1976):
Reporter to Apollo - Is it a coincidence that you're fighting a white man on our nation's birthday?
Apollo - Is it a coincidence the challenger is fighting a black man on our nation's birthday?
So, Rocky was written as a white character who is also Italian-American (most Italian-Americans are white).
And Apollo Creed was written as an African-American character who is HW champ. Creed was obviously influenced by real-life champ Muhammad Ali. In fact, if Ali had never existed, it would be difficult for me to accept Apollo Creed as a good, realistic character. Apollo Creed was basically Muhammad Ali but without the Nation of Islam bits.