However, because the Kiso Genji army was not used to naval battles and it suffered an utter defeat by the Heishi Suigun Navy at the Battle of Mizushima in Bicchu Province (Kurashiki City, Okayama Prefecture).
しかし海戦に不慣れな木曾源氏軍は、備中国の水島の戦い（岡山県倉敷市）で平氏水軍に惨敗。