Coaches on the field during a game

[Warrenkicker]

2-30-10 A non-player is a coach, trainer, other attendant, a substitute or a replaced player who does not participate by touching the ball, hindering an opponent or influencing the play. See 9-6 for illegal participation.

9-8-3 A non-player shall not be outside his team box unless to become a player or to return as a replaced player. A maximum of three coaches may be in the coaches’ area.

So a coach is a non-player and non-players are not allowed to be outside the team box except to become a player. So a coach, by rule, may never be on the field except during an authorized conference.