As the captain of the tennis team, Tezuka is serious about everything he does, and is very strict; one of his trademark phrases is "Don't let your guard down" ("Yudan sezu ni ikou") and to Ryoma "You will become the Seigaku pillar of support" ("Omae wa Seigaku no Hashira ni nare"). He is known for his seriousness, strictness, and fair leadership as the captain of the team. Tezuka often sacrifices his injured left arm to defeat opponents. Tezuka is known for his calm and serious exterior.