To encourage the soldiers of the 'western' army, who were frightened by a report that Ieyasu arrived at Akasaka, Mino Province, though he was considered not to be able to move from Edo in fear of betrayal of Kagekatsu UESUGI of Aizu and Masamune DATE in the north region, Sakon led a squad of 500 soldiers to fight against the 'eastern' army of Kazuhide NAKAMURA and Toyouji ARIMA (Battle of Kuise-gawa River) in the evening before the Battle of Sekigahara in 1600, and his squad and the squad of Takenori AKASHI (vassal of Hideie UKITA) won a complete victory.
慶長5年（1600年）の関ヶ原の戦いの前日には、会津の上杉景勝、また北からの万一の伊達政宗の裏切りに備えて江戸からなかなか動けないはずの家康の美濃国赤坂到着の報に動揺する西軍の兵たちを鼓舞するために、兵五百を率いて東軍側の中村一栄・有馬豊氏両隊に小競り合いを挑み（杭瀬川の戦い）、明石全登（宇喜多秀家家臣）隊と共に完勝した。