Sadayuki Mizoguchi

Mizoguchi is serious, attentive and invested in both the performance and conduct of Aoba Johsai's players. He tends to react more openly than Nobuteru Irihata, particularly when a player makes an avoidable mistake.

He nevertheless understands that Seijoh's strength depends on players thinking independently. The team's experienced members are given room to read situations and alter their approach rather than waiting for instructions after every rally.

Mizoguchi also recognizes the unusual influence Tooru Oikawa has on the team and watches closely as the setter draws different performances from individual hitters.

Mizoguchi's established expertise is coaching and match observation rather than active play.

He monitors opposing strategies, evaluates Seijoh's performance and works with Irihata during matches. His sideline perspective allows him to identify changes in momentum and appreciate the tactical significance of individual plays.

Aoba Johsai's adaptable team-oriented volleyball reflects a coaching environment that gives experienced players considerable responsibility for solving problems themselves.

Mizoguchi appears throughout Aoba Johsai's competitive matches as part of its coaching staff. He observes Karasuno's development across repeated encounters and witnesses how Hinata and Kageyama's offense changes between tournaments.

His reactions from the bench frequently provide context for tactical developments and demonstrate how seriously Seijoh's coaches assess Karasuno despite its previous reputation as a fallen powerhouse.

Mizoguchi remains primarily an adult supporting figure, with his role centered on guiding Aoba Johsai rather than an independent storyline.

Nobuteru Irihata is Aoba Johsai's head coach and Mizoguchi's senior coaching partner.

Tooru Oikawa is the team's captain and setter, whose tactical decisions Mizoguchi regularly observes.

Hajime Iwaizumi is Aoba Johsai's vice-captain and one of the senior players Mizoguchi helps coach.