Shigeno Daigo is an elementary school student whose father, Goro, is a professional baseball player. Inspired by his father, who was once a Major League player, Daigo begins playing baseball with the Mifune Dolphins, a youth team. However, he struggles to meet the expectations of being the son of a professional and quits baseball after less than a year. Then, in the spring of his sixth-grade year, Daigo's school welcomes a transfer student, Sato Hikaru, whose father is Sato Toshiya, a former Major League player and Goro's close friend. The destinies of these two young men begin to unfold!
