NFL head coaches will now be able to designate an assistant to handle the task of throwing the red flag…NFL head coaches will now be able to designate an assistant to handle the task of throwing the red flag to challenge a call through instant replay. Since the current instant replay rule was put in place in 1999, only the head coach was allowed to throw the flag to challenge a disputed call. “The head coach or head coach’s pregame challenge designee can initiate a challenge by throwing a red flag onto the field of play before the next legal snap or kick,” the rule book says in Article 1 (a). If a head coach wants to give up those duties, he will have to let the officiating crew know before the game. The decision to throw the flag is typically made in consultation with staff in the coaches booth with the head coach having final say.