Tsuna is the only one left to be picked for his P.E’s baseball game. As the two teams argues on who should have him, Takeshi Yamamoto invites him to join their team. As the game progresses, Reborn watches Yamamoto from afar, saying that his popularity and athleticism are needed for the family. Although Yamamoto proves to be an amazing player, the team still loses due to Tsuna. As the team leaves Tsuna to sweep the field alone, Yamamoto arrives and helps him. As the two clean, Yamamoto asks for Tsuna’s advice concerning baseball. Tsuna is surprised to hear him ask him and tells him that he should just give more effort. After the two clean the field, Tsuna leaves while Yamamoto remains to practice.
At his room, Tsuna is asked by Reborn if something good happened at school. Tsuna tells him about Yamamoto and Reborn tells him to make him his subordinate to which Tsuna refuses, saying that he thinks Yamamoto is hot on baseball and that he only wants to help him as his friend. Reborn, however, has a different idea of hot…
The next day at school, Tsuna hears that Yamamoto is jumping off the building since he broke his arm during practice and thinks that it’s his fault. As the whole class goes to Yamamoto’s side, Tsuna hides from him. Reborn then arrives and uses his Dying Will Bullet on Tsuna who runs and is seen by Yamamoto. Tsuna tries to reason with Yamamoto, saying that he was arrogant and that he is sorry. Tsuna then runs off again but Yamamoto is able to grab him causing him to slip and the two falls down the building. Reborn shoots Tsuna with his bullet and Tsuna is reborn in midair with the dying will to save Yamamoto. After Tsuna grabs Yamamoto, Reborn shoots another bullet to Tsuna’s hair whorl which causes his hair to grow and be used as a spring. The other students then leave thinking that it was only a joke by Yamamoto and insults Tsuna of being a pervert. However, Yamamoto thanks Tsuna and Tsuna is able to gain a close friend. However, Reborn thinks of it differently and thinks that Tsuna has acquired another family member.
Note: Bold + Italicized = First Appearance