On the early morning of April 20, Morimasa SAKUMA, who was an important vassal of Katsuie, made a surprise attack, exploiting a gap that Hideyoshi went to Mino province to attack Nobutaka ODA.
4月20日早朝、勝家の重臣・佐久間盛政は、秀吉が織田信孝を討伐するために美濃に赴いた隙を突いて、奇襲を実行した。