Maruo Eiichiro is an honor student in his first year of high school. He's a very methodical person who keeps two sets of notes for class and focuses entirely on his studies. One day, Eiichiro decides to participate in a free trial at South Tennis Club (STC) because he needs some exercise. There, he meets school idol and sweetheart Takasaki Natsu. Eiichiro has taken his first step into the world of tennis

The match between Eiichirō and Miyagawa begins with each holding serve. However Eiichirō feels that something is off. After studying his notes, Eiichirō realizes that Miyagawa has been studying his shots, and with a 4-3 lead he plans on making his move in the eighth game.

After defeating Miyagawa, Eiichirō returns to STC for some training that will make him better in 1 day. Eiichirō is teamed up with a Coach Mike from Florida who specializes in pyschological training.

Araya and Eiichirō end up at deuce after neither player can gain an advantage. An ace end up being huge for Araya give him the match point advantage, and despite his best efforts a lucky bounce proves to be the end for Eiichirō as he loses 6-1, 6-4. The finals are held between Araya and Takuma.

Yu Nabae matches up with Eiichirō and realizes they really are two players that are virtually the same. He realizes that what Eiichirō lacks is experience with the fundamentals, as he has never played anyone like himself, and after losing the first set Nabae begins to pull away and goes up 5-2.

Eiichirō runs to watch Natsu's match when he learns she is in danger of losing. Afterwards they return to STC where he Ryuhei Aoi, a man who will become his new coach.

Eiichirō and Natsu go out on their first date. When Eiichirō asks Natsu what she thinks about him, she tells him he is cheating. Afterwards Eiichirō is allowed to resume practice.