Haru Shirokane and Taiga are saved from a group of delinquents by the strongest XB player and leader of the Minato Tribe, Shun Kamiya. Despite calling him boring, Kamiya invites Haru to his Extreme Baseball team with Taiga joining too. In the match against a rival team. In the aftermath, Haru overcomes his weakness and decides to stay with Shun in the team.