The Karasuno High boys volleyball team have been through trials by fire to make it to Nationals. From being coachless to schools refusing to practice with “fallen champions”, these boys deserved a special kind of mentor to achieve their goal of reaching Nationals.
After relentless begging from theTakeda, the teacher supervisor of the volleyball club, Keishin Ukai, manager of the local Sakanoshita Market, eventually signed on to be the new coach of the team. Ukai is a former Karasuno alum and setter for the volleyball team. While he agreed to coaching only up till their practice game against Nekoma High School, Ukai stayed on for the sake of his boys' improvement.

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The Ukai Legacy
Keishin Ukai is the grandson of Ikkei Ukai, the legendary coach of Karasuno who lead them to Nationals in the past. When he retired from coaching, the team’s success dwindled and eventually became non-existent.
Fast-forward to the current volleyball team, Takeda tirelessly attempted to get Ukai on board to coach. Each time Takeda came by the Market, Ukai always turned him down because his grandpa was the famous coach and this role would be out of character for him. Apart from the famous Ukai name attached to him, Takeda pursued him for so long as a coach because in high school and college he excelled atmentoringunderclassmen and analyzing opponents' plays. To Takeda, Ukai is more than capable of coaching a high school volleyball team.

Ukai’s Stubbornness
As the new supervising teacher, Takeda has unsuccessfully tried to arrange practice games with other schools. It also does not help that the old Coach Ukai became estranged from other schools during his retirement, which distanced Karasuno’s relations with these schools. Because of the passion and promise of theteam, he finds it frustrating that he can’t bring these opportunities to fruition. He is candid about using the Ukai name to make these hopes a reality for the boys.
This turns Ukai away from coaching them even further, because he doesn’t want to “babysit” a bunch of teenagers. Takeda promises to keep returning, but guarantees that if Ukai just watched them play, he would understand Takeda’s desperation.

Ukai Comes Around
Another day, another begging session from Takeda. We learn that Ukai still loves volleyball, and even formed a Neighborhood Association of players. His reasoning for not wanting to go back to theKarasunogymnasium is because of nostalgia. He believes that the good times he had there should remain there. The place is too different from when he was in high school, therefore he refused to go back.
Takeda pulls out anAcecard to get him to join. He tells Ukai that Nekoma High, longstanding rivals with Karasuno for years, agreed to a practice game for the first time in five years. Coach Nekomata and the old Coach Ukai have been each other’s nemesis for years, which is why he agreed to practice match with Karasuno.

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During Ukai’s time at Karasuno, the relationship with Nekoma was at his strongest. The setter from 7 or 8 years ago from Nekoma has also been coaching the team lately. Ukai remembers him well, as he played against him during school. This new information riles him up immensely. It appears that the rivalry with Nekoma is definitely not buried and resolved. Instead, it is incentive for Ukai to coach the Karasuno team more than ever, at least until the practice game.

Ukai started off his coaching period with a bang. Not only did he just arrange a practice game, but he got his Neighborhood Association of older and fitter players to play with the team. He wants to gage how the boys play and where he can use them in strategy.
Ikkei and Keishin Ukai
Ikkei Ukai is the reason Karasuno was so successful. Because of his coaching, the school went to Nationals for the very first time. Keishin and Ikkei are very similar. From the use of nicknames (such as them both calling Hinata “Shrimpy”) to their coaching styles, the Ukais are natural mentors. They even resemble each other.
Ikkei can be rough with Keishin, throwing him around when they reunite after a while. However, Ikkei is greatly proud of hisgrandsonfor coaching the volleyball team. He praises him for his natural mentoring abilities. He attends their games and helps Keishin with his coaching from time to time.
Ukai and His Boys
Ukai can be just as childish and vengeful as the players on his team. Despite agreeing to coach until the Nekoma practice game, Ukai’s competitive deep-rooted rivalry with them resurfaces. He and the boys vow to get their revenge on Nekoma for beating them in the practice match. The only way to do that is to stay on as coach, which Ukai did till this day. It appears that Ukai was the perfect fit to coach this team, after all.