On the thirteenth day of the third month, Ieyasu arrived at Kiyosu Castle.
On that same day, warriors of the Oda clan's vassals who were led by Ikeda Tsuneoki switched to the side of Hideyoshi and took over Inuyama Castle, which had originally been built by Oda Nobunaga.
Ieyasu was upset upon hearing this news and rushed to Inuyama Castle, arriving two days later.
At the same time, Mori Nagayoshi (brother of Mori Ranmaru, who died at the Incident at Honnō-ji with Nobunaga) began his attempt for the Kiyosu Castle.
Despite fierce arquebus fire from Mori's men, Sakai Tadatsugu succeeded at flanking and attacking Mori in the rear.
Mori fled, having suffered 300 casualties.

On the sixteenth day of the month, forces called to support Inuyama Castle arrived in Haguro.
Ieyasu, however, had already known of these plans and had Sakai Tadatsugu and Sakakibara Yasumasa move 5,000 troops to Haguro that same evening.
Early the following morning, Tadatsugu's troops launched a surprise attack on Nagayoshi, whose troops barely escaped after the onslaught.
On the eighteenth, without fear of raids from enemies, Ieyasu took over Inuyama Castle and finished the defenses that had first been built up by Hideyoshi.
On the thirteenth day of the third month, Ieyasu arrived at Kiyosu Castle. On that same day, warriors of the Oda clan's vassals who were led by Ikeda Tsuneoki switched to the side of Hideyoshi and took over Inuyama Castle, which had originally been built by Oda Nobunaga. Ieyasu was upset upon hearing this news and rushed to Inuyama Castle, arriving two days later. At the same time, Mori Nagayoshi (brother of Mori Ranmaru, who died at the Incident at Honnō-ji with Nobunaga) began his attempt for the Kiyosu Castle. Despite fierce arquebus fire from Mori's men, Sakai Tadatsugu succeeded at flanking and attacking Mori in the rear. Mori fled, having suffered 300 casualties.
On the sixteenth day of the month, forces called to support Inuyama Castle arrived in Haguro. Ieyasu, however, had already known of these plans and had Sakai Tadatsugu and Sakakibara Yasumasa move 5,000 troops to Haguro that same evening. Early the following morning, Tadatsugu's troops launched a surprise attack on Nagayoshi, whose troops barely escaped after the onslaught. On the eighteenth, without fear of raids from enemies, Ieyasu took over Inuyama Castle and finished the defenses that had first been built up by Hideyoshi.
Battle of Komaki and Nagakute