Hiro Kunimi, Hideo Tachibana, and Atsushi Noda form a formidable trio on their middle school baseball team, leading it to consecutive national championships with an undefeated record. During this time, Hiro facilitates a relationship between Hideo and their childhood friend Hikari Amamiya, only to later realize his own romantic feelings for her. Hikari, in turn, begins to see Hiro as more than just a brotherly figure. Upon entering high school, Hiro and Noda receive a devastating medical diagnosis from a discredited physician, falsely warning that continued baseball participation would result in catastrophic injuries. Believing their dreams of reaching
Kōshien shattered, they enroll at Senkawa High School, which lacks a baseball team. Hiro joins the soccer team while Noda takes up swimming, while Hideo and Hikari attend Meiwa Daiichi High School, renowned for its elite baseball program. Senkawa's unofficial baseball fan club, managed by the earnest but accident-prone Haruka Koga, draws Hiro back to the sport during an impromptu match against the school's soccer team. Disillusioned by the arrogance of the soccer team's captain and star player, Hiro switches sides mid-game, nearly leading the fan club to an improbable comeback. This performance reignites his passion for baseball, and when the false medical diagnosis is exposed, he and Noda decide to remain at Senkawa. With Haruka's support, they persuade the school's skeptical headmaster to establish an official baseball team after a closely contested practice game against Meiwa Daiichi, which Senkawa narrowly loses due to questionable officiating. Under the guidance of novice coach Fujio Koga, Haruka's brother, the newly formed team faces Eikyo High School, a dominant program known for its ruthless tactics, including deliberate player injuries. Despite losing decisively, Senkawa's sportsmanship contrasts sharply with Eikyo's win-at-all-costs mentality. The following year, the team strengthens with new members, including Sagawa, a former delinquent with ties to Hideo, and two players initially planted as saboteurs by Eikyo's star pitcher, Hirota. All three ultimately embrace Senkawa's camaraderie and contribute significantly to the team's success. Senkawa avenges its earlier loss by defeating Eikyo in the divisional tournament, advancing to the national Kōshien tournament. A potential showdown with Meiwa Daiichi is thwarted when Hiro suffers an injury in the second round, leading to Senkawa's elimination. Meiwa Daiichi proceeds to win the summer tournament. Amidst these developments, Hiro confesses his long-standing feelings for Hikari, though he also grows closer to Haruka after defending her from harassment. Meanwhile, Hikari experiences personal tragedy when her mother passes away unexpectedly, deepening her emotional bonds with both Hiro and Hideo. The rivalry between Hiro and Hideo culminates in a Kōshien semifinal matchup. Hiro pitches a near-flawless game, holding Hideo hitless until the final at-bat, where a would-be home run drifts foul. Hideo strikes out on the next pitch, securing Senkawa's victory. In the aftermath, Hideo reconciles with Hikari, acknowledging his dependence on her, while Hiro implies to Haruka his aspirations for professional baseball, which she vows to support. Senkawa advances to the Kōshien final, leaving their ultimate fate undisclosed. ==Characters==