1. In previous CAS decisions, it has been established that CAS does not review "field of play" decisions made on the playing field by judges, referees, umpires and other officials, who are responsible for applying the rules of a particular game. An exception is nevertheless possible if such rules have been applied in bad faith. However, according to the CAS jurisprudence, it has been also clearly established that when a referee or umpire does not enjoy free discretion in his control of the game: he or she must comply with a game rule. A deviation by a referee or umpire from a mandatory game rule undermines the utility of the rule and, moreover, may affect the outcome of the game or the tournament.