Ko enters Seishu High School and joins the baseball club along with Akaishi and Nakanishi, where they are put on the second-string "portable" team headed by former Head Coach Maeno. Most of the varsity team are ringers recruited by new Head Coach Daimon from around the country, including power hitter Yuhei Azuma, the boy from the batting center, and Daimon promises Shido that he will take the school to the national spotlight of Koshien within three years. When Aoba, now captain of the junior high school team, visits a high school team practice, she is surprised to see Ko playing baseball, and he tells her he was inspired by her pitching. In class, Azuma does not recognize Senda (who is on the varsity team) but does remember Ko from the batting center. Azuma tells Daimon that he only remembers faces of significant people, of which there are four on the team. One day as the portable team practices on the junior high field, out of sight from the varsity players, Maeno has Ko pitch at full strength once and Aoba realizes Ko is Akaishi's "secret weapon" for getting off the portable team.
4月、星秀学園高等部に入学した光、赤石、中西。高等部の野球部では、新監督大門の方針で、野球留学生とテストに合格した者のみが1軍、それ以外を2軍として別けられていた。2軍は部室がなく、プレハブを拠点としているので、「プレハブ組」と呼ばれていた。光、赤石、中西の三人はプレハブ組に所属することになり…。
4월, 코우, 아카이시, 나카니시는 세이슈학원 고등부에 입학한다. 고등부 야구부는 새로운 감독 다이몬의 방침으로 야구 유학생들과 테스트에 합격한 사람들은 1군, 나머지는 2군으로 나뉘게 되고, 2군은 부실 없이 가건물을 거처로 하고 있어 '가건물 팀'으로 불린다. 세 사람은 가건물 팀에 소속되고, 어느날 감독으로부터 1군 승격을 건 연습시합이 있다는 소식을 듣게 된다.
