Yamato and Ace initially met as adversaries, clashing due to Ace's rampage on Onigashima. However, they quickly became friends after Ace realized that Yamato was being held captive by Kaidou. They bonded over drinks and discussions about the current generation of pirates, and Ace even told Yamato about his younger brother, Luffy. Before they parted ways, Yamato made Ace's Vivre card and kept a piece for himself so he could one day find Ace again. Yamato holds a deep respect for Ace, often stating that Luffy reminds him of Ace.