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This Russian sumo wrestler will not give autographs anymore. He has tested positive for marijuana and slapped with a lifetime ban from Japan’s ancient national sport. Two further Russian wrestlers were also banned for the same reason.

This is the latest scandal to rock the sumo world. Last year, a 17-year-old apprentice who wanted to quit was beaten to death by his trainer and fellow wrestlers. His dead body was covered with bruises and burns, there were cuts on his head and his ears were scratched. But for fans who are attending this autumn tournament in Tokyo, this does not seem to be much of an issue.

"These young people do their best to become number one. There might have been a few outbursts and, of course, violence is a bad thing, but I think it is good to train them in a very strict way," says one of the spectators, while another one, explains that violence is also a "tough-love technique". Tamakairiki has had his taste of tough love.

A former sumo, he began training at 14 years old and endured years of harsh treatment without complaining. "Training always used to begin when we were exhausted," he tells France 24. "Trainers used to pull us by our hair in order to make us stand. And if we opened our mouths, they would fill them with salt or sand, saying it was useless to complain. That was our routine."

Tamakairiki is now free to talk because he has retired.

A sumo wrestler does not protest, but endures such sufferings in order to become stronger. Those who speak openly are taking risks.

Yorisama Takeda, a journalist who has been covering Sumo for more than 20 years, is aware of this. "One day, a trainer wrote a book to explain how he had been involved in rigged competitions. He was about to give a press conference to foreign journalists, but he was found dead. On the same day, one of his cited witnesses was found dead as well, from the same cause," he says. "The story was never mentioned again. Those who are in charge of the media have close ties with the National Sumo Association’s leaders."

Yorisama Takeda is now involved in legal proceedings with the Japan Sumo Association. He is being accused of smearing the sport for having written articles about several scandals. But he refuses to be intimidated and fights for this traditional sport to regain the dignity it claims to stand for.