Sumire Ryuuzaki is the coach of Seigaku's tennis club and one of the school's math teachers. She helped Echizen Nanjirou develop his skills and become a professional tennis player. She has a granddaughter named Sakuno with a crush on Ryoma. Ryuuzaki has a rivalry with her ex-mentor, Banda Mikiya a.k.a. Banji, who is the coach for Yamabuki Chuu. She constantly yells, but she is considered to be a great, reliable coach. She has a good relationship with her regulars and participates in their recreational group activities: The bowling reunion and the beach-volley mini-tournament with Rokkaku Chuu.
- Age Lift: Inverted. She is actually portrayed by younger actresses in the Live-Action adaptations.
- In the 2006 movie, Sumire is played by J-pop singer Hitomi Shimatani and is Nanjirou's junior.
- In the 2014 Chinese series, Lin Qi (Sumire's name in the Chinese version) is instead Lin Ying's (Sakuno) aunt, is portrayed as Long Zheng Nan's (Nanjirou) classmate, and is older than the film version, but still younger than the original character.
- All There in the Manual: According to the Fan Books, coach Ryuuzaki is also a math teacher when she is not training the male tennis club.
- Badass Teacher: Do not be fooled by her age, she has taught her students right in the tennis club.
- Fan Disservice: Is a constant dealer of this to the team players. She even weaponizes it during volleyball!
- Hidden Depths: According to Sakuno, she learned how to bake because Sumire taught her, which her friends find hard to believe, since usually Coach Sumire, the teacher in charge of the male tennis club, looks scary.
- I Was Quite a Looker: When Nanjirou graduated and decided to go to America, she went to bid him goodbye at the airport in a red minidress. Apparently, she was such a hottie that one of her suitors was coach Mifune, from the U-17 camp.
- Not So Stoic: How can a friendly beach-volleyball mini tournament can be so unexpected with her Fan Disservice tricks?
- Related Differently in the Adaptation: In the Chinese Live-Action series, she and Lin Ying (Sakuno) are aunt and niece instead.
- Team Mom: She is the coach, teacher in charge, and only woman in the Seigaku Male Tennis Club. The regulars respect her a lot, and Kawamura is quick to protect her from a ball directed at her in the middle of a game.
- Unrelated in the Adaptation: In the 2006 film, she and Sakuno are not related. Instead, Sakuno is replaced by Shion Higaki, Egate's sister, who has no relation to coach Ryuuzaki.
Mikiya Banda or "Banji" for short, is Yamabuki's coach.
- Affectionate Nickname: Some of his students and even Sumire and Nanjirou, call him "Banjii" (which can be translated as "Old man Banda")
- Cool Old Guy: One of the few people capable of keeping Akutsu at line.
- The Gadfly: He pretends to have a stroke just to mess up a little with Coach Ryuuzaki.
- Perpetual Smiler: He always smiles. ALWAYS. So much that it creeps everyone out. And this sends Nanjirou in screaming fits.
- The Rival: He is this to Seigaku's coach Ryuuzaki Sumire, in terms of Team Coaching.
- Sitcom Arch-Nemesis: To Nanjirou. It only takes the mention of his name to set Nanjirou on a rampage.
- Team Dad: He is always there to support Yamabuki.
- Vague Age: Nanjirou gets shocked when he hears that Banjii is still coaching in Yamabuki Chuu, because he was already an old man when he was attending middle school.
Sakaki Tarou is the coach of Hyoutei's team. Sakaki is also a music teacher for the school and has complete confidence in Atobe Keigo, trusting that he is capable of defeating any opponent.
- Bunny-Ears Lawyer: Very efficient coach and music teacher. Just as quirky as his own pupils.
- The Dandy: He is refined, stoic and is always seen in fancy suits, even while coaching the tennis club.
- Catchphrase: "Itte yosh!"
- Stern Teacher: He is very strict, to the point of changing regulars if they loose a match even once. He only made the exception with Shishido because it involved an Important Haircut from Shishido, Ohtori's pleas and Atobe asking him personally. He later keeps the same regular team for the National Tournament.
Aoi Hanamura is the coach of Jousei Shonan, who refers to her students as masterpieces and constantly tries to recruit new students, especially Ryoma. She is often proud of her own prowess and of her pupils', but is otherwise very calm and professional.
- Ascended Extra: In the manga, she doesn't appear at all, where the only we see about her is her name in the Jousei Shounan list. She gets design and characterization in the anime.
- Bunny-Ears Lawyer: Fawns over her pupils almost like a teenage girl, when she's not coolly supervising their training menus.
- Insistent Terminology: She calls her students "masterpieces". Coach Ryuuzaki doesn't like this because it dehumanizes the boys.
- Ms. Fanservice: Big breasts? Check. A pretty face with a beauty mark? Check. Nice red hair? Check. A melodious mezzo-soprano voice? Check. Tight clothes when not at work? Oh baby, Check, Please!.
Ojii is the coach of Rokkaku Chuu. He is an elderly man who manufactures creates special wooden racquets for his players, taking into consideration their skills and personality.
- Cool Old Guy: The boys of the team and the kids adore him. He gathers so much respect from the local children at Chiba that most of them end up joining the tennis team.
- The Mentor: To the Rokkaku kids, who would later join the tennis club.
- Only Known by Their Nickname: Everyone only refers to him as "Ojii" ("Grandpa").
- Team Dad: He not only cares and trains his boys at Rokkaku, but also makes them their wooden racquets and inspires them.
- Vague Age: According to Nanjirou, he was already an old guy when he was attending middle school. Nanjiro also tells Ryoma that Oji was already old when the Black Ships came to Japan, according to rumors.
Osamu Watanabe is the coach of the Shitenhouji tennis club. Watanabe reminds us of a younger (and hipper) version of Yamabuki's Banda Mikiya. Like the latter, the former's interaction with his students is very laid-back, often shown joking around with them. Watanabe is also pretty sly. When the team first learned of Chitose Senri's resignation, Watanabe appeared ambivalent about the issue.
During the match against Seigaku, knowing how much the team needed Chitose and how much Chitose wanted to play Tezuka Kunimitsu, Watanabe "dragged" Chitose back onto the team. This and other incidents show that despite his appearance, Watanabe knows what he is doing. Osamu gave Shiraishi a gold gauntlet to wear until graduation.
Watanabe is shown to be either cheap or poor, telling his team that he'll treat them to somen noodles if they win against Seigaku (as opposed to Ryuuzaki Sumire, who told her team she'll treat them to yakiniku).
- Bunny-Ears Lawyer: Despite the fact he looks like a bum and is in general a very relaxed guy, he is actually a very capable coach who knows how to handle the tennis club different personalities.
- First-Name Basis: All his students always call him "Osamu" rather than "Watanabe-sensei". Not that he minds.
- Foil: To Hyotei's coach Sakaki Taro. While both are very competent coaches who care and know how to work with the students, their overall personalities are opposites. Sakaki is more stern, The Stoic, The Dandy, while Osamu is more carefree, relaxed, and looks like a hippie.
- Oral Fixation: He always has a toothpick on his mouth.
- Team Dad: He truly cares for his team's players. He also treats them to food, even if it's cheap.
- Trickster Mentor: He would do anything to motivate his students, even if that implies fooling them.
- Instead of accepting Chitose's form to resign the club, he just went ahead and registered Chitose for Doubles 1 anyway. This ended up motivating Chitose since he got to challenge Tezuka.
- In Another Story II, he purposely lied to the team telling them they needed to recruit Zaizen, so Shiraishi could figure out that they needed to diversify the team.
Saotome Harumi is the ruthless Higa Chuu tennis coach. He isn't above dirty play and won't hesitate to instruct his players to aim balls to the rival team's coach.
- Jerkass: He would instruct his players to hit rival coaches with the ball. After his team lost in the Nationals, he basically abandoned the regulars and left them to figure out how to return home on their own.
- Sadist Teacher: He is the only known teacher to be mean and tough to his students.
- Smug Snake: He doesn't care about anyone as long as his team wins.
- Would Hit a Girl: He didn't hesitate to instruct Hirakoba to aim at Ryuuzaki Sumire in the middle of a game.
