However, while Yoshitsugu was changing his course from the Hokuriku area to Mino Province, Takatsugu suddenly switched to the East side, led his 3,000 soldiers to Otsu-jo Castle and fortified the defenses there.
ところが高次は吉継が北陸から美濃国へと転進する最中に突如東軍に寝返り、手勢3000名を率いて大津城に籠城し防備を固め始めた。