Yumichika Ayasegawa vs. Shūhei Hisagi

 was one of the battles that occurred during the Ryoka Invasion.

Prelude
As the 11th Division captain and its members assisted the Ryoka and were searching for Ichigo Kurosaki, Yumichika Ayasegawa and Kenpachi sensed an ominous presence indicating that there was someone hiding nearby. Kenpachi calls them out. Captains Sajin Komamura of the 7th Division and Kaname Tōsen of the 9th Division show themselves along with their respective lieutenants, Tetsuzaemon Iba and Shūhei Hisagi.

The others in Kenpachi's group are surprised to see them as Tōsen asks why Kenpachi is aiding the Ryoka. Yumichika mentions to Makizō Aramaki that they have them outnumbered for a fight, but Kenpachi states that he will be the only one fighting by taking them on 4 vs 1. Komamura and Tōsen both comment that Kenpachi is much too prideful while Kenpachi insists that they all come at him at once. As the rest of the group wonders what to do, Lieutenant Yachiru Kusajishi tells Kenpachi that the rest of them will continue on as he fights. As Kenpachi says he’ll catch up to them, Tōsen remarks that he can’t be serious, and that he must have lost his pride and his sanity. Kenpachi simply replies that he never had any sanity to begin with. While the group runs ahead, both Hisagi and Iba step forward and offer to fight Kenpachi first. As Kenpachi grumbles about how his opponents were looking down on him by not coming at him all at once, Ikkaku Madarame and Yumichika step in. Kenpachi asks the two why they did not leave with the others, only to be ignored as Ikkaku yells at the lieutenants that they are not good enough to fight their captain as he and Yumichika would be sufficient opponents. Seeing that his two officers wanted to fight as well, Kenpachi lets them have Hisagi and Iba as opponents. Ikkaku motions for them to move to another location, to which Yumichika agrees and asks Hisagi for approval. Hisagi simply replies that it makes no difference. They then leave.

Battle
As Hisagi fights Yumichika, he notices the manifestation of Tōsen's Bankai. Wondering on the reason of his captain's use of Bankai, he concludes that he needs to return to aid his captain as soon as he can. However, Yumichika interjects, claiming that he has not lost yet. Hisagi dismisses Yumichika's claim to which Yumichika responds that only death is considered a loss in the 11th Division. As Hisagi notes how different the 11th Division is from the 9th Division, he chides Yumichika for thinking a 5th Seat Officer could defeat a lieutenant (and on how Yumichika would probably not want to die in such a boring fight). Yumichika responds simply by explaining his division's philosophy is to fight well before dying as death is inevitable for everyone. He then decides to tell why his rank is a 5th Seat Officer and the unofficial rule of the 11th Division on how one's Zanpakutō must be a melee-combat-type to be considered a true member of the Eleventh Division. Yumichika then quickly turns the tables by releasing his Zanpakutō's true Shikai, which he had hid from everyone.

Aftermath
It is soon revealed that Yumichika had emerged victorious as he was walking around looking for his captain. Upon encountering Kenpachi, he asks if he had won his respective battle. Kenpachi responds back by saying that Komamura had left the fight to go assist Captain-Commander Genryūsai Shigekuni Yamamoto. Noting on how happy Yumichika sounded, Kenpachi turns and sees that Yumichika had won without any injuries (although he had to go make a change in clothes). Hisagi is then seen, collapsed in exhaustion and disbelief. Hisagi wonders how such a Zanpakutō could exist as his Reiryoku was completely sucked dry.