三方原之戰
By 1567, the majority of daimyō forces in the Tokugawa armies were organized in two divisions, each with a separate commander. Kazumasa was placed over the forces of 13 Tokugawa daimyō-vassals and his counterpart, Sakai Tadatsugu, was given command over the forces of 18 daimyō-vassals. He participated in the 1572 Battle of Mikatagahara. and 1575 Battle of Nagashino.