Jisaburō Ozawa
The Battle of Saipan began on 15 June 1944. The IJN, under Vice Admiral Jisaburō Ozawa, was overwhelmed within days by the U.S. 5th Fleet in the decisive Battle of the Philippine Sea, where Japan lost three fleet carriers and about 600 aircraft. Nagumo and his Army peer Lieutenant General Yoshitsugu Saito were now on their own to keep control of Saipan.