We can't say he is done, but he will need to show so much mental toughness to overcome this. You got to understand a fighter with the run volk has is mentally invincible. No way did he imagine even King Kong could knock him out.
He now knows that a heavy shot can render him unconscious and no matter how mentally strong you are? It's always on the mind
Manny pacquiao was knocked out cold in 2012 by his nemesis Juan Manuel Marquez. Now Manny went right back on the saddle and put a beating on Rios his next fight. But the next time he faced a counter puncher with great timing (Floyd) he didn't fight his usual style. He threw less shots than normal and rarely charged in because you better believe that heavy right hand from Marquez was on his mind. If he never got knocked out, he would have been all over Floyd like a cheap suit
Volk is not getting any younger, but this is definitely going to play on his mind. He seems to be very strong mentally as a fighter and personally I think he can recover