Yamabuki isn't a school of huge tennis tradition, but the last year they had reasonably good results thanks to red-headed ace Kiyosumi Sengoku and their good doubles players. Their trump card, though, is the newest addition to their line-up: The utterly rebellious and EXTREMELY skilled Jin Akutsu. Their coach, Mikiya Banda aka Banji, is known and feared/respected for his Manipulative Bastard status.
Kiyosumi Sengoku, also known as "Lucky Sengoku", is a third year student, and is one of the keys to Yamabuki's strategy of finishing opposing teams off quickly. He is a happy-go-lucky guy with a strong tennis sense and extremely sharp eyes able to discern fast moving balls. He is known as a National level player, and was invited to the Junior Senbatsu (Junior Selection) training camp in his second year after Tezuka declined. Despite those honors, he suffered losses to both Momoshiro in the Prefectural tournament and Kamio in the Kanto tournament. After a certain point, he throws away his old style of tennis, trains in boxing, and forms "Boxing Tennis", which focuses on the three-minute limit in a boxing round.
- Bunny-Ears Lawyer: Off-court, he seems primarily concerned with flirting with women. On-court, he's one of the most skilled players in the series, shutting down Kamio's speed and giving Momoshiro a hard time.
- Catchphrase: "Lucky~!"
- Chick Magnet: He is very popular with the girls on his school.
- The Face: He is not only the best player of the team (aside Akutsu), but he is also charming enough to be the most popular guy on school.
- Handsome Lech: He has a pretty face, and he is popular... but he is really into dating them.
- The Nicknamer: He calls Momoshiro "Omoshiro-kun", which is a wordplay on "Interesting guy", as a sign of him not taking Momoshiro seriously throught the match.
- Number Two: He is Vice-Captain of the Yamabuki team. He also is the second best player after Akutsu. However, according to the room arrangements in New Prince of Tennis, Higashikata is the Vice-captain instead.
- Signature Move: "Kouhou".
- Western Zodiac: He carries around an Horoscope book to be up to his luck for the day and is constantly talking about lucky numbers, colors and signs.
Jin Akutsu is something of a punk, who was called a "once-per-decade" tennis player and known as a monster. A very cynical person, he hates to be bossed around and punishes those who order him to do something. He is very violent, attempts to cause conflict constantly. He uses an unusual flexibility of his body to put high speeds on his shots and hit balls in unnatural positions allowing him to hit his opponents if he desires. He was trained in tennis at young age, but gave up after finding it boring, until being recruited by Mikiya Banda under the promise of being able to hurt others.
- 10-Minute Retirement: Quits tennis after losing to Ryoma during the prefectuals, but is back to playing by the time the U-17 camp rolls around thanks to Banji relentlessly badgering him.
- The Atoner: In New Prince of Tennis: U-17 World Cup, he takes all the damage from Amadeus, to the point he even starts bleeding and dying his sneakers red. The team realizes that this is his own way to atone for all the pain he caused while playing.
- Badass and Child Duo: Downplayed Trope. Dan is Older Than They Look and the age difference ain't huge (Dan's 12-to-13, Akutsu is 15). But if you looked at them without knowing it, you'd swear they play it straight.
- Badass Normal: Is the only one among the Japan middle schoolers who can hit ten balls, but has no muga (like Echizen Ryoma) or special abilities (like Toyama Kintaro).
- Berserk Button: Do NOT defy him or give him anything similar to an order. Only Dan can do that, and that's because he's Dan.
- Big Damn Heroes: When Kawamura almost falls victim to the elder Ishida's powerful shots and ends launched towards the seats, Akutsu catches him.
- Brilliant, but Lazy: His animalistic speed and reflexes meant that he could coast through the his matches without doing any training at all. He's so uninterested in actually putting work in to the point that he gives up tennis after his very first loss.
- Catchphrase: "Don't order me."
- Delinquents: Akutsu is big, violent, intimidating, skips classes, smokes and beats up people for no reason.
- Delinquent Hair: He has bleached spiky white hair.
- Expository Hairstyle Change: As a pre-teen, he had a brown bob. As an older teen, he's got spiky white hair.
- Even Bad Men Love Their Mamas: Despite getting in trouble regularly and worrying her constantly, Akutsu only agrees to join the U-17 training camp because her mother took the effort to gather all the pieces of the shredded invitation and put them together. Akutsu finds her asleep while gluing all the pieces.
- Foil: He's just like Ryoma as an arrogant newcomer wild card who joins the team. But while Ryoma is generally aloof, Akutsu is more unrestrained and violent.
- Forgotten Childhood Friend: Kawamura's. Akutsu lived near the Kawamura Sushi and Kawamura was one of the few people who could approach him without getting punched.
- Good Smoking, Evil Smoking: In one of the fanbooks, there's a section on what some of the characters carry in their bags. It's blurred out, but you can faintly tell that it's a packet of cigarettes.
- Jerkass: He is a punk that doesn't want to be ordered around, you wouldn't be expecting much on that regards...
- Jerk with a Heart of Gold: After his defeat in the Prefectural Torunament, it's clear that he also worries a lot for his loved ones, even his friends (as Kawamura and Dan).
- Licked by the Dog: It's clear that having sweetie little Dan around has somewhat influenced him.
- Odd Couple: In The New Prince of Tennis, Sanada requested him as his doubles partner, since he believed his wild and unpredictable style would contrast well enough with his methodic and disciplined game.
- Sleeves Are for Wimps: Both his regular jacket uniform and his tennis team t-shirt are sleeveless.
- Took a Level in Badass:In The New Prince of Tennis he comes back and beats Kawamura in a 7-1 match. Akutsu is among the first of the middle schoolers to hit ten balls with ease.
- Unskilled, but Strong: Sorta. While he does have good skills, his forte are his borderline animalistic speed and reflexes.
- What the Hell, Hero?: To Ryoma in the anime, after his humiliating defeat against Sanada.
- Worthy Opponent: Banji uses the promise of him finding one in order to lure him into the tennis club.
Kentarou Minami is the captain of the Yamabuki tennis club. He is a doubles player who typically plays with the vice-captain, Higashikata Masami. Together, they are known as the Jimmies, referring to jimi "(地味)", the Japanese word for plain or dull.
- Anime Hair: His spiky hair doesn't seem to be natural.
- The Captain: He is the captain of Yamabuki's Tennis team. However, he is often overshadowed by some of his own teammates (Akutsu and Sengoku).
- Embarrassing Nickname: "Jimmies" (dull/plain). He gets called this along with his doubles partner, Higashikata.
- Overshadowed by Awesome: He is the only captain who doesn't have a special aura or technique. Also, despite being the captain, the most prominent players on Yamabuki are Sengoku and Akutsu.
- Ridiculously Average Guy: Lampshaded In-Universe, where others label him, along with Higashikata, as "Jimmies" or "The Plain Guys".
- In The New Prince of Tennis, he and Higashikata are specifically asigned to Atobe and Kadowaki's room, with the explanation that the room is composed by "Two arrogant personalities and two plain personalities".
- Supporting Leader: He is the captain, yet not the best player in the team. Also his speciality is Doubles games, working well along Higashikata.
- Those Two Guys: With his doubles partner, Higashikata.
- Embarrassing Nickname: "Jimmies". He gets called this along with his doubles partner, Minami.
- Number Two: He is Vice-Captain of the Yamabuki team, according to the room arrangements in New Prince of Tennis, despite Sengoku being established to be the Vice-captain during the Regionals team order sorting.
- Ridiculously Average Guy: Lampshaded In-Universe, where others label him, along with Minami, as "Jimmies" or "The Plain Guys".
- In The New Prince of Tennis, he and Minami are specifically assigned to Atobe and Kadowaki's room, with the explanation that the room is composed by "Two arrogant personalities and two plain personalities".
- Those Two Guys: With captain Minami.
Taichi Dan is a 1st year student and the manager of the team. He believes he is worthless because of his size and looks up to Akutsu because of his strength. Akutsu tells him to become stronger, which leads to him joining the team as a player. He is also inspired by seeing Ryoma play, realizing that even someone who is short can excel in tennis. He wears a headband that was given to him by Akutsu.
- Catchphrase: "Dadadadaan!" and "Ussodaan!".
- Cute Sports Club Manager: Male example. He initially settles as just manager since he believes his skills aren't enough to make it to the team. Later he trains hard to get on the regulars.
- Dude Looks Like a Lady: He is smaller than the rest of the team, has a feminine hairstyle and a cute voice.
- Hachi Maki: Given to him by Akutsu. Since it's too big for him, he is often seen pulling it up.
- Hero-Worshipper: He is this towards Akutsu. He even keeps Akutsu's headband.
- I Just Want to Be You: In an anime filler, Dan gets to train with Seigaku for a day, and he tries to imitate Ryoma in everything, even buying a cap like his. He eventually gets over this while playing against Ryoma.
- Keet: Cheerful, enthusiastic and positive.
- Morality Pet: To Akutsu. Akutsu is noticeable less mean to him.
- Older Than They Look: Dan's not nine or ten. He's at least twelve.
- Plucky Girl: Gender-inverted. Even though Akutsu is mean and rude to him and scares other people, Taichi is the only one who isn't intimidated by Akutsu and keeps following him around.
- Suspiciously Similar Substitute: Only in The New Prince of Tennis. Dan takes Kachiro's role (while Shiita essentially replaces Katsuo) in the new "Freshmen Trio" with Horio, when they get into the U-17 Training Camp (in secret).
- Tagalong Kid: He is the only 1st year who follows closely the regular team as the manager. He's later seen tagging along with Akutsu everywhere.
- Verbal Tic: "-desu".
- Cool Shades: He is almost never seen without his sunglasses.
- The Unfought: He is placed for Singles 1, but he never gets to show his skills, since Seigaku wins three matches before his match against Tezuka.
- Offscreen Moment of Awesome: He and Kita beat Fuji and Kawamura in Doubles 2 offscreen.
- Those Two Guys: With Kita.
- Offscreen Moment of Awesome: He and Nitobe beat Fuji and Kawamura in Doubles 2 offscreen.
- Those Two Guys: With Nitobe.
