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

Eiichiro is unable to answer Natsu when she asks him what he enjoys doing most. He becomes interested in tennis and returns to STC for another free trial. This time, he meets Egawa Takuma, an upperclassman who's friendly with Natsu. For some reason, he acts hostile towards Eiichiro, which is very intimidating. As Takuma watches, Natsu teaches Eiichiro how to hit the ball.

Eiichiro is unable to forget how good it felt when he successfully returned Takuma's serve, and he spends all of his time practicing against the wall. After seeing Eiichiro practice against the wall non-stop for six hours on a Sunday, Natsu predicts that he will quickly improve.

Eiichiro finds himself in a contest with Takuma. Eiichiro has fifty tries to return Takuma's serve. One successful return and Eiichiro wins. However, despite Eiichiro's best attempts to follow his notes and stick to the basics, he can do nothing against one of the strongest serves in the country.

Eiichirō is about to play his first match. He receives advice from the other STC members, but it only makes him more nervous. He doesn't get a chance to calm himself down as he's soon called to the tennis court. His first opponent is Oobayashi Ryo, a player with five years of experience, the assistant captain of the tennis team at Shonan Tech, and a top eight finalist in the prefectural tournament. It's finally time for Eiichirō's first match! This episode covers chapters 8, 9, and 10 in the manga.

It is down to the final match of the set. Eiichirō trails 5 games to 1, but with a determination to stay on the court as long as possible Eiichirō begins to push Oobayashi. Coach Miwa notices that Eiichirō has sharp eyes and is able to predict his opponents next move when he is focused. The final match lasts close to an hour, and in the end Eiichirō is unable to score a single point in the final match. Oobayashi learns this was Eiichirō's first match and begins to fear what Eiichirō will become if he is diligent with practice while gaining control and more muscles. The next day Eiichirō returns to the Kanagawa Junior Circuit, despite having been eliminated, to study various tennis playing styles. Coach Miura notices him there and tells him if he really wants to improve, he should come to STC the next morning at 7 AM. This episode covers manga chapters 11, 12, and 13.

In order to improve Eiichirō's playing, Coach Miura has him learn control on a 9-square court. After getting the basics done, Eiichirō is forced into a match against Takuma. Takuma realizes that Eiichirō has gained control but proceeds to show Eiichirō that control and good eye site is nothing compared to experience. Coach Miura then instructs Eiichirō and Takuma to continue playing each other as often as possible. 3 months after the Kanagawa Junior Circuit, Coach Miura asks Eiichirō to sign up for the Championship Match Tournament to see how much he has improved.

Maruo Eiichirō continues his training at STC as he tries to master every shot. At smaller tournaments he begins advancing to the third round but is unable to go further. His mother worries that Eiichirō is spending too much time on tennis when he drops out of cram school to practice more. Eiichirō begins calling Natsu Nat-chan. After one year of playing Maruo prepares to return to the Kanagawa Junior Circuit and make it past the third round, but in order to do so he'll likely have to defeat three seeded players.

Eiichirō returns to the Kanagawa Junior Circuit. His first match is up against fellow high school student Koshimizu Nariyuki, a man whom is always trying to compete with Eiichirō for the top scores. Eiichirō is a little too tense and quickly falls behind 3-0 when he finds a note from Natsu at the back of his notebook talking about what to do if he feels too tense. With this help Eiichirō rebounds and wins 6-3, beginning a process that would take him into a third round match with 5-seed Miyagawa. However Miyagawa is confident and proclaims he has learned Eiichirō's weakness after watching one match. Match 2 begins as Eiichirō takes on the 52-seed Noborikawa. With no tension Eiichirō easily advances with a 6-1 win. After the match Eiichirō watches Miyagawa's match to see what his tennis style is truly like to get him ready for the 3rd round.

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. If Miyagawa manages to break Eiichirō in the 8th game, the set will be all over. Instead of getting too depressed, Eiichirō changes his strategy and starts playing serve and volley tennis. The change of pace allows Eiichirō to win Game 8 and even it at 4-4, but will either competitor manage to break serve, and will Eiichirō be able to find his winning shot before it becomes too late?

After managing to hold serve Eiichirō starts looking for an opportunity to break Miyagawa. Both hold serve and force a tiebreaker. With the score 6-5 Maruo in the tiebreaker Eiichirō decides to try and gamble to use his full stroke and steal a point. The gamble backfires and Miyagawa evens the score 6-6. However Eiichirō's gamble makes Miyagawa think too much during his serve. He falls victim to a double fault, giving Eiichirō the match point opportunity on his serve. Seeing no other choice, Miyagawa makes a move to the net to catch Eiichirō by surprise. However Eiichirō's racket happens to be in the right spot for a return from short distance. Eiichirō's miracle return gives him the tiebreaker 8-6 and the match 7-6. The crowd is shocked as the 5-seed has been knocked out.

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. Mike is envious of Eiichirō's notes and points out his notes will help him recall his shots faster, and that he only has 20 seconds to recall his best memories. Eiichirō is able to master this basic training of Mike, and in round 4 he defeats the 16-seed Terashima with relative ease. A broken string forces him to go to the tennis shop where he meets his quarterfinal opponent, 3-seed Iwasa Hiromi. Hiromi doesn't seem to have any interest in Eiichirō. After Hiromi leaves, the shop owner explains that Hiromi doesn't get to know his opponents in advance. Instead he learns and draws an image of them while they're playing on the court. Eiichirō is confused by this and wonders how someone can draw pictures while playing.

The match between Hiromi and Eiichirō begins. Everytime Eiichirō tries to go on the attack, Hiromi hits a shot Eiichirō can't reach. Hiromi goes up 1-0, but then Eiichirō realizes if he lets Hiromi complete his masterpiece and then returns the final shot, he will win the point. Eiichirō manages to go up 5-2 when Hiromi begins to increase his speed. Hiromi cuts it back down to 5-4. Eiichirō envisions his best match, the match against Terashima, and with that vision he comes up with a plan he believes will allow him to move on to the semi-finals.

It is match 10 of a 1-set match, and Eiichirō leads 5 games to 4. Eiichirō begins to up his speed against Hiromi, and with it he stays even at 30-30. Just then Hiromi's legs cramp up, allowing Eiichirō to get two easy aces and win the match 6-4. After the match Hiromi announces he is going to focus less on tennis and start drawing more on the canvas. However he tells Eiichirō that he appears to have the same desires to go Pro that a lot of the other top 4 do, even though he is currently only playing for the fun of it. Eiichirō scouts Araya only for Araya to win 6-0 and then tell Eiichirō he will crush him in the next match. The semifinals are set to occur in 2 days time, so Eiichirō uses that evening and the next day to practice. Coach Miura tells Eiichirō he needs to focus on his tennis style instead of trying to play to Araya's game and makes him take practice easy. The day of the semifinal comes, and Miyagawa comes to cheer for Eiichirō. Miyagawa helps Eiichirō realize that looking for an opponents weakness actually helps that opponent improve, so Eiichirō decides to ask Takuma what Araya's weakness is. When he finally finds them, he sees Araya whispering something to Takuma that could change the entire outcome of the future.

Eiichirō overhears Araya telling Takuma that if he loses to him this tournament, he will retire from tennis. His plan is to defeat Takuma and then announce he is going pro. Takuma agrees to tell Eiichirō Araya's weaknesses. Eiichirō comes up with 5 steps that give him the first game in a 3-set match. After going up 30-0 in game 2, Araya protests a point and receives a warning. However the protest allows Araya to get into the zone. Araya manages to win the next 6 games with ease and goes up 1-0. In set 2 Eiichirō studies all of Araya's shots from set 1 and realizes he can predict Araya's movements. Down 1-0 in set 2 Eiichirō finally manages to reverse Araya's counter shot and go up Love-15. How will this exciting match end?

After going up Love-15, Araya uses a number of service aces to go up 3-1 in set 2. Eiichirō holds serve, and as he gains a 30-40 advantage in Game 6 of Set 2, Araya punches himself in his face to eliminate his emotions from the game. Both players manage to hold serve, giving Araya a 5-4 advantage in what could be the final game. Eiichirō decides to gamble and begins to predict where Araya will hit his shots. With the two even at 30-30, Araya serves knowing that whichever player wins the point will hold the advantage for the rest of the match.

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. Takuma plays to his best ability and once again prevails, 4-6, 7-5, 7-5 to win the championship. As Eiichirō returns to his bag he runs into an unknown youngster named Ike Souji. Ike asks to see Eiichirō's notes before running off due to an important phone call. However he asks Eiichirō to inform Coach Miura that he will soon be visiting STC. After the awards ceremony is held, the others vow to defeat Eiichirō in the All Japan Junior before Eiichirō says he can't participate due to his low showings the year before. However he swears he'll get ready for the Inter-High. As Eiichirō gets home, he gets rewarded for his performance, but he shocks his parents when he asks them what they'd think if he decided to go Pro at tennis.

Eiichirō investigates going Pro, but his reaction from his parents is less than he expected. Eiichirō joins Natsu at the first round of the All Japan Pro to watch the debut match of Ike Souji. Afterwards he puts together a presentation for his parents on going Pro and asks for one year where he won't have to study or attend cram school so he can make the All Japan Junior. Should he fail to win the All Japan Junior, Eiichirō will turn his entire focus to studying. After gaining approval Eiichirō informs his coaches at STC, who come up with a hellacious schedule, both for practice and for tournaments, that will qualify him for the All Japan Junior. At the end of the episode Ike Souji appears to greet his old friends at STC, and after getting approval from his coach, manager, and doctor he gets 10 minutes of practice time with each STC member who volunteers to face him. When his doctor, coach, and manager disappear, Ike grabs a hold of the ball and asks Eiichirō to play a practice match with him during the remaining time instead of just hitting the ball back and forth.

Eiichirō manages to steal 1-point in the 10-minute match with Ike before his coaches reappear and make him stop playing a match. Afterwards Eiichirō is sent home to rest. The next day Eiichirō begins a brutal practice regimen that will recondition his body into that of a pro's. After 2 weeks of practice Eiichirō is invited by Coach Miura to come view some of the top seeds at the All Japan Junior. Eiichirō finds a fellow kindred spirit in terms of note taking and is shocked to learn he is the 2-seed. Eiichirō quickly realizes his data will allow him to control his opponents shots if his body gets conditioned correctly.

Eiichirō participates in a tournament after 3 months of hellish training. He learns about active rest while participating in the tournament and makes it to the final. Terashima is his opponent. Eiichirō shocks Terashima with how his game has changed and manages to win 6-1, 6-0. In all of his matches the closest game was 6-2. After the match Coach Miura informs Eiichirō he will have a week off before they do another 3 weeks of hellish training. He informs Eiichirō that this type of training will continue for the rest of the year, with him eventually getting down to only two days of rest inbetween. With a week off, Eiichirō helps his school perform their yearly cultural festival, a festival which ends up serving only to bring him and Natsu a little closer.

Eiichirō continues his practice and gets his next tournament schedule. As the last player to qualify he is placed up against the 1-seed, Yu Nabae. Eiichirō begins to look for weaknesses from Yu on tape, but what he finds is a highly adaptive style that could easily beat him if he doesn't come up with a few tricks.

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.

In an effort to try and reverse the tide, Eiichirō decides to go back to his idea of having 100-squares to aim for instead of 9. The precision allows him to begin winning some points, but more often than not Nabae watches balls go out and gets some easy points. How many games will Eiichirō manage to win against Nabae, and will he be able to gain a break?

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. At first he doesn't trust Ryuhei's words, but he is even more shocked when Coach Miura says all of his training is being turned over to Ryuhei, and Ryuhei won't let him do any practice the next two days.

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. He learns how important it is for your ego and your subconscious to match up evenly. Coach Ryuhei decides the only way Eiichirō can meet his goals is to go to Florida during the winter break.