In May 1979 he was a runner-up for the fourth time, to Wakanohana with a 13–2 record. He followed that up with a superb 14–1 record in the following tournament, defeating Wakanohana, Kitanoumi and Wajima, only losing the championship in a playoff to Wajima on the final day. In September 1979 he was finally promoted to "yokozuna". The 97 tournaments it took him to do so is the slowest ever progress to sumo's top rank. His "oyakata" declared that he would be happy with just one more "yūshō" before Mienoumi's retirement. In the event, Mienoumi won his second and third tournaments as "yokozuna", the latter with a perfect record, but after this had several absences due to injury and illness, fighting a full fifteen bouts in only four tournaments as "yokozuna", before retiring in November 1980. He has the lowest win-loss ratio of any post-war "yokozuna".