In order to maintain his newfound status as Champion, Ippo must defend his title against some of the toughest boxers in the game. His latest challenge is against Sanada Kazuki, a former Jr. Featherweight champion and medical student. Adding to the intensity of the match, Sanada is being coached by Ippo's old rival Hama Dankichi and works at the same hospital as Kumi, Ippo's love interest. With everyone at the hospital rooting for Sanada, Ippo not only has to win the match to keep his title but also to win back Kumi's heart.