Coach Aoi explains to Eiichirō that he stopped the match against Takuma because his body wasn't developed to serve like Takuma yet. If he had continued to serve that way, he would have injured himself and forced himself to give up his tennis career. In order to use his new weapon of serving Eiichirō is given strict training that will develop his arm muscles and increase his speed. At school the career counselors call for all seniors to determine their future careers, and Eiichirō lists his desire to go Pro, noting that he will turn to college if he doesn't win the All-Japan Junior.
Après son match interrompu contre Takuma, Eiichirô entame un entraînement intensif pour améliorer son service en vue du tournoi du Japon. Au programme, étirements et renforcement musculaire pour gagner en rapidité malgré un manque de carrure et de puissance. Nat, elle, participe aux sélections du tournoi indoor junior au cours duquel elle doit affronter Aki Shimizu, tête de série n° 1 du tournoi, contre laquelle elle n'a encore jamais gagné.
逞（たくま）との戦いでサーブの重要性に気づいた栄一郎（えいいちろう）は青井（あおい）コーチと特訓に励む。そして３学期が始まり、進路について考える栄一郎は両親と全日本ジュニアで優勝できなければプロを諦めると約束したことを思い出し、決意を新たにする。そんな中、栄一郎は全日本ジュニア選抜室内選手権の偵察に行き、試合を見てさらに気合いが入る。そこで偶然、奈津（なつ）のライバル・亜希（あき）と出会う。
