However, when the Kokufu side built an alliance with the Dewa Kiyohara clan in 1062, the Abe clan was pushed into an inferior position, leading to the beheading of Sadato after being lost in the Battle of Kuriyagawa in September.
康平5年（1062年）、国府側が出羽清原氏と結ぶと劣勢となり、9月には厨川の戦いに敗れて斬首された。