The pro-bending referees are officials who enforce the sport's rules at the Pro-bending Arena in Republic City during the matches. There are at least two referees present during each match, each tasked with different duties. One is the head overseer of the game while the other serves as more of a linesman.
When AvatarKorra made her debut in the pro-bending ring alongside her Fire Ferret teammates Mako and Bolin, the referees were on duty for the match. As the Avatar had never been in a pro-bending match before, she was not familiar with the rules. In the opening seconds of round one, she used waterbending to knock one of her opponents over the side of the ring, which was not allowed by the rules of pro-bending. The referee called a penalty and ordered Korra to move back to zone two. Soon afterward, he pointed out that she was over the line and administered another one zone penalty. When she exposed herself as the Avatar by earthbending, the official once again called a penalty, but this being the first time the Avatar had stepped into the ring, he was not entirely sure how to deal with the situation. Eventually, the referee allowed her to continue participating under the condition that Korra would restrict herself to the use of only water.
A referee later officiated the Fire Ferrets' quarterfinal match in the tournament against the Boar-q-pines. After the teams split rounds one and two, he declared round three a tie, forcing a one-on-one tiebreaker round. He tossed a coin which would allow a team the first choice of who to send up for the round, which was won by the Fire Ferrets.
After the Buzzard Wasps scored a decisive victory in round one of the semifinals of the Pro-bending Championship Tournament and gained the advantage in the second round, Korra bent water up from the ring's trough to grab the opposing firebender by the leg for a throw. She then proceeded to continue bending water at her from below. The referee called a penalty for unnecessary roughness and ordered Korra to move back one zone. Korra responded that she would "unnecessarily rough [him] up" and waterbent a sizable blast in his direction. The referee then gave her a yellow fan warning.
During the championship match of the tournament, the White Falls Wolfbats committed a series of fouls which the match's referee seemed to ignore. Mako believed that the official had been paid off, while the fans booed him and Shiro Shinobi pointed out their mistakes over the radio. The referees' mistakes allowed the Wolfbats to claim their fourth consecutive pro-bending championship.