“NFL’s game operations manual, which details how the games are run, including rules regarding the national anthem.
According to the game operations manual, the national anthem must be played prior to every game, and all players must be present on the sidelines when it is played.
It also says that players on the field and bench area, stand at attention, face the flag, hold helmets in their left hand, and refrain from talking.
Rule 4, section 2 of the NFL’s rulebook in regards to game timing also states that both teams should be on the field 10 minutes prior to the game’s scheduled kickoff. ”