However, when the West squad was razed in the final battle on October 21, Yorifusa secretly held a meeting of betrayal with the East squad led by Ieyasu TOKUGAWA in Ogaki-jo Castle according to advice from the vassal Yorimori INDO.
しかし、9月15日の本戦で西軍が壊滅すると、家臣の犬童頼兄の進言を受けて、徳川家康率いる東軍に大垣城にて内応した。