The school's team desperately wants him to join so they can defeat their rivals at Gedo High, but Jubeh, bearing the heavy emotional scars of accidentally killing his father during a game of catch, refuses (this bit of personal history is told in flashback and narrated in song by Jubeh himself, stumbling through a minor key).
Jubeh eventually agrees to be the pitcher, but on the day of the big game, Gedo High murders every single member of the team, including Jubeh, who shows up late and steps on a land mine that is buried in the field for some reason.
This is what happens when you use BabelFish to translate the rules of baseball into Japanese.
This turns out to be no more than a minor setback, however, because, through a combination of divine intervention, advanced cybernetics and time-bending reincarnation, everyone is more or less fine and ready for a rematch (please note that by this point in the movie, not one game of baseball has taken place).
After beating his mother with a baseball bat, Jubeh suddenly remembers how to do his special move, the Super Tornado Pitch (yes, that sentence just happened and now belongs to history).
We feel sorry for those of you at work who want to shout "HADOUKEN!" right now, but can't.