The general customs of football do not approve the intentional punching or striking of others. That this is prohibited was supported by the testimony of all of the witnesses. They testified that the intentional striking of a player in the face or from the rear is prohibited by the playing rules as well as the general customs of the game. Punching or hitting with the arms is prohibited. Undoubtedly these restraints are intended to establish reasonable boundaries so that one football player cannot intentionally inflict a serious injury on another. Therefore, the notion is not correct that all reason has been abandoned, whereby the only possible remedy for the person who has been the victim of an unlawful blow is retaliation.