In 1343, given the order from KO no Morofuyu, who was the senior vassal for Takauji, he attacked Seki-jo castle in Hitachi Province protected by Chikafusa KITABATAKE, Munesuke SEKI, and Munemasa SEKI of Southern Court (Japan) power, although succeeding his military exploits, he got injured badly from this battle and soon died afterwards (It is also said that, while taking part in the plan to dig the tunnel to make their way inside the Seki castle, they were attacked by the castle guards, and was killed when trying to escape).
1343年、尊氏の重臣・高師冬に従って南朝(日本)勢力である北畠親房・関宗祐・関宗政が守る常陸国関城を攻撃し、奮戦して大いなる武功を挙げたが、このときの戦いで重傷を負い、まもなく死去した（坑道を掘って関城を攻略しようとする作戦に参加したが、城兵に看破され敗走する際に討ち取られたとも）。