A ball? Give them swords!
While things like sucker punches and kicks to the head are prohibited, headbutting, punching, elbowing, and choking are all allowed. But imagine for one second your opponent was allowed to knock you out cold and it was within the rules of the game.
Every time you turned around you could be met with a kick to the head, or an elbow to the jaw. There is little doubt you have to be tough to play sport, but there are only a few tough enough to ever give The Calcio Storico a go .