Sumo grand champion Harumafuji has announced his intention to retire after his assault of a junior wrestler.
The 33-year-old Mongolian-born "yokozuna" issued an apology earlier this month after media reported he had beaten Takanoiwa while drinking at a restaurant-bar with other wrestlers.
The reports added that Harumafuji had become incensed when he saw the younger wrestler checking his mobile phone after being chastised for having a bad attitude.
The incident tainted the image of the national sport just as it was regaining popularity.
It has has highlighted the ancient sport's struggle to reform harsh conditions that can breed violence in its closed, hierarchical world, although some wrestlers say there have been improvements in the decade since 17-year-old trainee Takashi Saito was beaten to death by other wrestlers.
"Sumo, recognising its responsibility as the sport with the longest history in Japan, must stamp out violence so that the expectations of the people, including youth, are not again betrayed," Education Minister Yoshimasa Hayashi, whose ministry oversees sports, said in a parliamentary committee meeting.
A Japan Sumo Association spokesman said Harumafuji's "oyakata" (head coach) Isegahama had informed the JSA of the wrestler's decision on the grand champion's behalf.
The head of an advisory body to the JSA, the Yokozuna Deliberation Council, had said this week the affair warranted "extremely harsh punishment" but did not issue a final decision because both the JSA and police were still investigating.
"There is almost no doubting that an act of violence was carried out," Masato Kitamura, chairman of the panel, told a news conference after a council meeting on Monday.
"The general feeling within the council is that a strict disciplinary measure is required."
