Mitoizumi was ranked at "sekiwake" on several more occasions and won seven special prizes, but the highlight of his career came in July 1992, when he took the top division tournament championship for the only time. Ranked at "maegashira" 1, he took advantage of the absence of the top ranked wrestler at the time, "ōzeki" Akebono, and clinched the championship on the 14th day with a win over Takanonami. He finished on 13-2, two wins ahead of his nearest challengers Kirishima and Musashimaru.