Nev. Admin. Code § 467.132
An unarmed combatant who fails to appear in a contest or exhibition in which he or she signed a bout agreement to appear, without a written excuse determined to be valid by the Commission or a certificate from a physician designated by the Commission in advance in case of physical disability, is subject to disciplinary action. An unarmed combatant who files a certificate from a physician designated by the Commission stating that he or she is unable to fulfill a bout agreement because of physical disability shall, on being restored to the eligible list, fulfill the bout agreement with the same opponent or a suitable substitute specified in the bout agreement within a reasonable time, as determined by the Commission, unless the unarmed combatant is released from the bout agreement by mutual agreement.
Nev. Admin. Code § 467.132
NRS 467.030