Sendo has held the Japanese featherweight following a questionable win over Volg Zangief (that even Sendo himself didn't accept gladly) to decide who would take the Featherweight Championship vacated after Eiji Date retired, defending it twice by KO. Ultimately not only would he lose the title to Ippo in their rematch but as a result of Ippo's devastating punches, he was shelved due to Ippo cracking his ribs with body blows and Liver blows. Despite their Rivalry, and Sendo's desire to avenge his losses, he has become good friends with Ippo as the series has progressed.