Shuuji Sagawa

A year younger than Hiro and the others, he was Hideo's childhood friend, and the younger brother of the person that taught them both baseball. Acts and talks like a punk, but is a gifted shortstop. Bears a grudge against Katsutoshi Hirota for framing him and kicking him unfairly off the middle school baseball team, and joins Senkawa High's team to get revenge.

(Source: AdachiFan)