The referee inside a professional sumo ring is called a gyōji.
A gyōji wears traditional court-style clothing and carries a fan called a gunbai. Before a bout, the referee announces the wrestlers, manages the pre-bout preparations and gives the commands that begin the contest. During the action, the gyōji follows the wrestlers closely and indicates the apparent winner with the gunbai.
The referee’s decision can be challenged by ringside judges, who are senior sumo officials. If they believe the result or timing is unclear, they may hold a mono-ii, a judges’ conference, and review what happened. The gyōji’s judgment is therefore important but not absolutely final.
Gyōji also perform ceremonial and administrative duties within the Japan Sumo Association. Their elaborate dress is different from that of yobidashi, who call wrestlers to the ring and help maintain the arena. The two roles are often confused because both are visible during tournament bouts.