Possibly. But no guarantee that it showed from day one — I would guess he would have had an aptitude but I seriously doubt everyone stopped hitting the bags, sparring came to an abrupt halt and all turned and said, ‘This is him, the Chosen One.’
You aren't going to magically change your genetic make-up/quantity of (fast/slow) twitch fibres, by punching as fast as you can on a bag, pads or ball