However, when he and his troops took a rest at Mt. Okehazama on the way to the castle, they were attacked by Nobunaga ODA, and even though Yoshimoto fought hard with Soshin MATSUI, he was decapitated by a vassal of the Oda family named Yoshikatsu MORI, and his favorite long sword inscribed Sozasamonji was taken.
ところがその途上、桶狭間（おけはざま）山で休息中に織田信長の攻撃を受け松井宗信らと共に奮戦するも、織田家家臣・毛利良勝に愛刀・宗三左文字の太刀ともども首級を奪われた。