Hakuho, who won a record 45 tournaments in his career before retiring in 2021, is being criticized for failing to act against the violent behavior of one of his students.
Hokuseiho, like him of Mongolian origin and aged 22, is accused of hitting teammates and stealing money from them.
According to Japanese media, the Japanese Sumo Association (AJS) will meet on Friday to decide the fate of the "master", who claims that he knew nothing of the actions of his student, who risks retirement.
He faces the most serious punishment in the sumo world
“Master” Hakuho risks a financial sanction and above all a demotion to the lowest rank in the hierarchy of retired sumotori.
After dismissal and retirement, demotion is considered the most serious punishment for sumo veterans.
In this traditional Japanese sport, sumotori live in community, with their “oyakata” (master) and his wife, in a “heya” where they sleep in a large common room.
In recent years, the world of sumo has been tarnished by multiple violence scandals.
Last July, a former sumotori denounced the mistreatment suffered over nearly eight years in the world of sumo, with physical violence and regular bullying.
In 2009, a former master was sentenced to six years in prison for encouraging three of his recruits to beat a 17-year-old apprentice, who died of his injuries.