Any superstar makes enemies as well as friends, but few have alienated so many people as Asashorya, the reigning champion of sumo wrestling.

At 26 he is one of the most successful wrestlers in the sport’s history, and one of its most controversial.

Sumo is meant to breed dignity and restraint but Asashoryu swaggers into the ring like a 148kg (23st), loincloth-clad cowboy. He smirks when he wins a bout. After losing he has been known to barge into his opponent.

Above all, in a sport that is regarded as the quintessence of Japanese culture, he is a Mongolian, the most successful of a growing horde of foreign wrestlers. So there must have been as many smiles as frowns when scandal broke over Asashoryu. For the past two weeks a Japanese magazine has published allegations that in a tournament in the city of Nagoya last year he systematically bribed his way to victory.

In Nagoya Asashoryu achieved a clean sweep, winning all 15 of his bouts. Nowadays Weekly magazine quotes unnamed wrestlers who accuse him of paying up to one million yen (£4,200) to his opponents to lose deliberately.

The magazine describes how he is alleged to have made the match-fixing deals through a lower ranked, fellow Mongolian wrestler named Kyokutenzan. It names the 11 wrestlers whose matches are alleged to have been rigged. “Asashoryu is happy to buy sumo matches whenever he wants to win the championship,” it writes.

The sport’s ruling body, the Japan Sumo Association, last week questioned Asashoryu, currently the sport’s only yokozuna or grand champion, as well as its four ozeki or champions. All have denied knowledge of match-fixing. The association has yet to announce its findings but Asashoryu angrily denied everything.

“I have never done anything like that,” he told reporters after his interrogation. “Since I was an ozeki they have written stuff about me but I am not guilty of anything. It is really upsetting and terribly sad that after getting my 20th title victory they write something like this.” Asked if he planned to sue the magazine, he replied: “You betcha!”

Allegations of match fixing have swirled around sumo before. In 1996 two former wrestlers went public with such claims — mysteriously, they both died soon afterwards on the same day, in the same hospital, both of heart failure. Four years later when another wrestler told tales of cheating, he wisely went into hiding. The Sumo Association has always denied such charges and the articles in Nowadays offer little to prove it this time around.

Asashoryu’s accusers are identified by letters rather than their names, and the suspicious behaviour cited by the magazine is less than convincing — sightings of Kyokutenzan visiting the changing room of Asashoryu’s opponents shortly before their bouts. Could the story be a concoction by some of his many detractors?

“It’s possible — just because he is so strong,” says Kunihiro Sugiyama, a sumo commentator. “That creates jealousy.

“The fact that he’s a foreigner gives people a harder attitude towards him. But we have to face up to his great strength. At the moment Asashoryu is stronger than the Japanese.”

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