"The Duck's Determination" is the fifth chapter in Ahiru no Sora.
After their intense brawl with the troubled seniors of Shinmaruko High, Sora and Momoharu head to the school's basketball court for some practice. While seeing Kurumatani's three-pointers, Momoharu asks Sora how he can improve his shooting skills. Sora explains that he is a feeling type of basketball player. Hanazono, unable to understand, jokingly throws the ball at him.
Sora explains further that every person has their unique way of shooting depending on their personality and thinks Momoharu's shooting form isn't bad. He needs to work on his accuracy. He then further explains that he always shoots the ball for it to go in. Kurumatani making his explanations complicated makes Hanazono furious, and a small argument takes place.
Meanwhile, Madoka enters the basketball court and watches all the action between them unfold. She starts to smile at their friendly argument; Momoharu tells her to leave and not interfere. Yabuchi is also amazed when the two of them became good friends all of a sudden. Hanazono asks Madoka that didn't the girls' team have a match today. Yabuchi stated that it got canceled. Momoharu informs Madoka that the seniors of Shinmaruko High challenged them to a basketball match, and he is thinking of seeking permission from their schools' advisor. At the locker room, Sora informs his other team members of the upcoming practice game. Upon hearing Yasuhara, Nabe and Chucky gets furious and ask Kurumatani are they looking for another fight. To calm his seniors, Sora explains that they can consider this upcoming practice match a form of fighting and tells them, let's show Shinmaruko High their way of basketball.
Yasuhara, Nabe, and Chucky are inexperienced members of the team. Either of them knows nothing about basketball rules, and they have never participated in an official match. Kurumatani takes them to court and tries to teach them the basics of dribbling. While dribbling the basketball from Yasuhara's hand slips and hits Chucky in the forehead, and the girls' team members of Kuzuryu High start to laugh at them. Embarrassed by it, the three leave the court and tell Sora that they are not participating in the match. Momoharu tells Sora not to stop them, and the game is next week, and it would be impossible for the three of them to learn all the basics. After practice, Momoharu, accompanied by his brother Chiaki goes to the nearby shoe store and purchases a pair of new basketball sneakers. Chiaki asks Momoharu that his behavior has changed lately and how he managed to buy these shoes since both of them get the same allowance. Hanazono responds unlike Chiaki, he is a thrifty person, and ever since Sora has joined the team, basketball hasn't been boring anymore.
The following day Sora requests Yasuhara, Nabe, and Chucky to reconsider playing basketball. They don't give a proper response; Kurumatani tells them he will clean the locker room and buy buns. Yasuhara responds that they will reconsider playing if Kurumatani will go to the gym without pants. Sora took it even further and entered the court without wearing any clothes, everyone is shocked, and Yasuhara, Nabe, and Chucky agreed to participate in the upcoming practice game. Meanwhile, at the Kanagawa Hospital, where Sora's mom (Yuka) is getting treated for illness receives a message from her son that he will be participating in a basketball practice match.
- Sora Kurumatani
- Momoharu Hanazono
- Madoka Yabuchi
- Ryuuhei Nabeshima
- Yasuhara Shinichi
- Masahiro Saki
- Chiaki Hanazono
- Yuka Kurumatani (flashback)