He later captured Numata-jo Castle and became its Keeper, and when the Castle was attacked by Ujikuni HOJO, he performed brilliantly in repelling the attack with the help of a relief army from Kagekatsu UESUGI.
さらに沼田城も攻略し城代となり、北条氏邦の侵攻を受けるが、上杉景勝の援軍を得てこれを撃退するなど活躍した。