Character Role Analysis
Stanley is a tricky antagonist, as we discuss in more detail in his "Character Analysis," because we can see how Blanche antagonizes him, too (the whole racist slang thing and trying to convince Stella to leave him, for example).
But any way you cut it, Stanley is still the play’s antagonist. He’s violent and, of course, enemy to our protagonist, Blanche. The scene where he hits Stella is evidence number one, and of course the rape is evidence both number one and two.