Kazuya Miyuki becomes the catcher for Sawamura in a contest against Seido's dangerous clean-up batter, Kiyokuni Azuma. As Eijun tries to pitch down the middle, he finds himself tense and unable to control the ball. Kazuya immediately calls time and comes out to give him some words of encouragement. The words have the desired effect as Eijun finds more control than ever before and unveils a dangerous weapon he didn't know he had. Seeing how people like Kazuya can alter his pitching, Eijun decides to come to Seido as long as he can become the ace of the team.

The Seido baseball club has been invited to the spring invitational at the hallowed Koshien Stadium. Sawamura will finally stand on the mound! Standing between Seido and the national title are the winners of last year's summer tournament Komadai Fujimaki and their unstoppable ace Masamune Hongo. Can Seido triumph over Komadai? It's the start of another heated battle in youth baseball!

Seido has made it to the fourth round of the Tokyo Spring Tournament. With East and West Tokyo competing, there are some interesting games coming! Teito, a school that has played many times at Koshien Stadium and defeated the reigning champions Inashiro in last year's fall tournament, is facing Ugumori who have been getting lots of attention. The winner of this game will play Inashiro in the fifth round! It will be a match to see!

After their own semifinal game the nine Seido players watch Inashiro's semifinal against Teito. Narumiya and Mukai both played at Koshien Stadium as first-years, and then received their powerhouse school's ace number as second-years, and they'll both be pitching. Meanwhile, Seido High School is analyzing their game against Ichidai Third High, focusing on Coach Kataoka. Then, Miyuki remembers a certain thought...

Seido’s first string returns from the golden week practice games. Due to Sawamura’s outstanding performance in the Hakuryu match, an article about him was published, making his presence known. Coach Kataoka hands out baseball journals with some comments about the practice games written in them. Sawamura’s comments from the coach serve to motivate him to work harder, while Furuya’s compels him do some self reflection. The team practices fielding with the coach.

It's the final innings of the game against the Wynd Youth. Following Narumiya's masterful relief pitching, the other Inashiro players, Carlos, Shirakawa and Yamaoka have really shone. Miyuki is reminded how imposing his rival team is. Meanwhile, in Seido's practice game against Yamamori, Yui is wearing the catcher's after Ono had to leave the field. Several walks and battery errors are making the game difficult. Yui blames himself for throwing off Furuya's rhythm.

Seido awaits their first game of the summer tournament. Sawamura wants to get used to wearing the ace number and so begins to sleep in his uniform, earning him a teasing from his roommates. Coach Kataoka receives an stimulating call from his former mentor Coach Sasaki, the coach of Yura Sogo Engineering High School who they are about to face. Yura Sogo competes in the first round anticipating their game against the seeded Seido. What does the cunning Coach Sasaki have up his sleeve?

It's the top of the seventh inning in Seido's game against Hachiya Oji. Hachiya Oji has to score this inning or else the game will be called. Kawabata fought his way to a base, but it would be Hachiya Oji's last offensive. Seido's victory is imminent. After hearing Furuya say he'd get to play next game, Sawamura watches the game from the bench, the number one on his back. The story of these two players vying for the title of ace will continue.