The fourth season finally enters the American chapter. Goro goes to the United States alone to become an American professional baseball player. He encountered a little trouble as soon as he got off the plane, and a college student named Hayato Yaginuma helped him. Yagi and Goro are determined to become professional baseball players, so the two of them took the entrance examination for the professional group Sammons together... Goro's journey forward is full of difficulties. Standing on the 3A pitching board, he has to confront a hitter who is destined to meet. The hitter's name is Joe Gibson Junior, the son of "Gibson Junior". For some reason, he inexplicably hates Goro. Why is this? In the fourth season, Shouya and Meimura who become professional players, Komori who continues to play baseball after entering college, Shimizu Taikawa who succeeds the captain of the Seihide baseball team, and Goro's opponents and teammates will all appear. Please look forward to it!