I can't imagine being a football player and a boxer is good for his health. I would think these are the sports with the highest risk of head trauma. Does he plan to keep boxing or is he gonna return to football?
Has he stated what he hopes to accomplish by boxing? This sport is nothing to play around with. And though it is impressive that a NFL player has three professional wins, he will be seriously hurt by anyone with a pulse. It's too late for him.