The fact that the NFL continues to battle the problem of poor manners serves to highlight the innate gentlemanliness that characterizes football’s main rival as “THE American sport”: baseball. In baseball there is both a respect for other players and for the game itself that is missing in football and indeed in any other major sport. Baseball singularly entails an unwritten code, which consists of three elements: (1) Do not show anyone up; (2) Do not cause serious physical injury to another player; (3) Try your best (4) Do not cheat. A general adherence to this code means that baseball requires less legalistic regulation than football and other sports.
Stephen Klugewicz, “The League of Extraordinary Gentlemanliness” at The Imaginative Conservative. For an example of the code at work see what happens to a batter who “flips” his bat on hitting a home run. Watch.