On May 2, the Taira navy under the command of Tomomori sallied forth from Hikoshima in response to Yoshitsune's attacking navy, and at the hour of the horse (about noon - according to the "Gyokuyo chronicle"; the "Azuma kagami" claims it was during the morning) the two navies clashed at Dannoura in the Kanmon straits, and the battle was joined.
3月24日、攻め寄せる義経軍水軍に対して、知盛率いる平氏軍が彦島を出撃して、午の刻（12時ごろ）（『玉葉』による、『吾妻鏡』では午前）に関門海峡壇ノ浦で両軍は衝突して合戦が始まった。