TOKYO - Already reeling from the antics of a rogue grand champion, Japan’s national sport of sumo now has to deal with a suspicious death.

Japanese police are considering charging the trainer of a 17-year-old sumo wrestler who died earlier this year on suspicion that a beating during a practice session may have caused the fatality.

Tokitaizan, whose real name was Takashi Saito, collapsed after practice on June 26 while preparing for July’s Nagoya Grand Sumo Tournament.

The boy’s father, Masato Saito, wants to get to the bottom of exactly what happened to his son.

“Firstly, I want to know the truth,” Saito said at a press conference Thursday. “I don’t want this kind of accident to happen anymore — I want my son to be the last one.”

Police have questioned the trainer, or stable master, Tokitsukaze, 57, and the other wrestlers in his stable after deciding Saito’s injuries did not appear consistent with those sustained in practice.

On Friday, Japan’s education ministry ordered a full-scale investigation into the matter.

Senior vice minister of education Kenshiro Matsunami said there could be possible punishment against those implicated in the case and ordered the Japan Sumo Association to take steps to avoid a repeat of such a scandal, ministry officials said.

Saito died at a hospital on June 26 and at his family’s request, police conducted an autopsy that showed the body had numerous bruises and wounds.

Tokitsukaze, whose real name is Junichi Yamamoto, has said he struck Saito on the head with a beer bottle the day before he died, and forced him to train so hard that he could barely stand the day of his death.

Fellow wrestlers told authorities Saito had injured himself while training.

According to the boy’s father, members of the Tokitsukaze stable called his family and offered to cremate Saito’s body before the family got to see it. The Saito family declined and the body was sent to Saito’s house.

The family was shocked to see cuts and burns on his body.

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According to Saito, his son fled from the training facility twice, once in mid-June and again on the day before his death but did not tell his father that he had been bullied or assaulted.

Adding to the suspicion is the fact that Takashi’s mobile phone, which could have contained information about the situation surrounding his death, was broken in two and it remains unknown who broke it.

Because of their excessive weight, sumo wrestlers, even in their youth, are susceptible to a variety of health problems but this doesn’t appear to be a factor in Saito’s death.

The coroner listed the numerous bruises and wounds as the likely cause of death.

The Saito case is just the latest blemish for Japan’s national sport.

Grand champion Asashoryu is serving a two-tournament suspension for playing in a charity soccer match earlier this summer in his native Mongolia, after skipping an exhibition tournament. He claimed he was injured.

Following his suspension, Asashoryu suffered a nervous breakdown and flew back to Mongolia for treatment after sumo officials berated him for skipping an official appearance.