[ctdonath2]

Players were threatened for kneeling on the field during a game, so there’s plenty of precedent for threatening them for kneeling on the field during a game - on grounds that both irritate/offend many in the audience.

[Alberta's Child]

NFL rules and the collective bargaining agreement are very clear about what happens on the field, and how a player dresses on the sideline -- to the point of being almost pathologically meticulous. Just read the rules governing the color, design and logos on a player's cleats, for example.

However, it looks like there is nothing in the NFL's rules or in the collective bargaining agreement that covers a player's behavior on the sidelines before the game begins.

This will almost certainly be addressed when the CBA expires and a new one is negotiated.