I disagree.
Would not a woman be considered battered, because she only took one punch from a man? Or how about a Mike Tyson placing one punch with his bare fist?
In any event, one punch resulted in a foreseeable result of the affected person hitting the ground.......which is hardly an indirect result.
If you throw a punch, you are responsible for the end result.
I don't disagree with either of your comments but what I do disagree with is that one single punch - no matter its efficacy or consequences - constitutes a "beating" in the normal sense of the word.
Again, I agree that one punch constitutes "battery", and one punch from Mike Tyson would likely result in a KO (but NOT, I submit, a beating), and I also agree that everyone is responsible for their own actions.