Japan's scandal-hit sport of sumo has vowed to cut all ties with the yakuza gangsters ahead of the basho, or tournament, now taking place in Tokyo. But has irreparable damage already been done?
If you have ever wondered how sumo wrestlers build up their great bulk and power, the answer can be found in the restaurants that cluster around the great sumo stadium at Ryogoku in Tokyo.
They specialise in the pork meatballs and vegetables stewed in a miso soup base that wrestlers eat in vast quantities.
Most sumo wrestlers are still relatively poorly paid, and when they get too old to endure the ring many opt to open a chanko nabe restaurant.
Kotonofuji Oyakata's place is typical. Trophies vie with bottles of sake for space on the shelves.
Customers sit at low tables on the tatami mat floor, many of them still ask for his autograph, he says.
The walls are lined with photographs of the wrestler in his prime - some as a hulking teenager when he first entered the stable for training, others taken later when he was competing.
After a lifetime in sumo the allegations of the sport's link to yakuza gangsters are no surprise to him.
"It's natural," he says. "It's show business, they organise show business.
"Even in traditional Kabuki theatre there is a famous character, a sumo wrestler who becomes a yakuza. So the link has always been there."
But the Japanese expect wrestlers to live up to strict standards of good behaviour.
Sumo is more than two large men trying to push each other out of a ring; its origins are in Shinto rites performed in temples.
Traces of its sacred purpose can still be seen when wrestlers throw handfuls of purifying salt before a bout.
So when links to the yakuza were thrust very firmly into the public eye this year there was consternation among fans.
One of the two top Japanese wrestlers was expelled, and many more were suspended, over illegal betting allegedly organised by gangster middlemen.
In July the national broadcaster NHK refused to broadcast the Nagoya Basho live - the first tournament it has missed in more than half a century.
Jake Adelstein, author of Tokyo Vice: An American Reporter on the Police Beat in Japan, believes the scandal is just part of a much wider police offensive against the yakuza.
"The yakuza represent traditional Japanese values; honour, loyalty, reciprocity, endurance, obedience," he says.
"The yakuza have portrayed themselves as preserving those values. In that sense they are kind of admired. So in order for the police to drum up support for new laws to really crack down on the yakuza, the police needed to show they are doing something awful.
"And to take Japan's national sport and turn it into a scandal-ridden entity, that really doesn't sit well with the Japanese people."
For decades the yakuza have been able to operate with extraordinary openness, expanding their operations from running red light districts to property deals and stock market manipulation.
The gangsters have business cards and offices that are listed in the phone book.
Some have established structures rivalling great corporations in size. The largest, the Yamaguchi-gumi, is 40,000 strong.
Fan magazines and comics have been published for people to keep up with the latest goings-on in the underworld, which is also a popular subject for films and soap operas.
In return the police appear to have expected the yakuza to be discreet, avoid street crime, and to make sure civilians were not caught up in any violence.
The thinking in Japan seems to have been if there has to be crime at all, better it be organised.
But there have been reports that some gangsters have started to renege on the deal in recent years, refusing to allow the police to visit their headquarters, which was common practice, and even collecting information on officers' families.
And last year they went too far when dozens of yakuza ostentatiously sat in the VIP seats at a sumo tournament to cheer up a gang boss watching the live coverage on television in his prison cell.
It was the final provocation for the National Police Agency.
"Yamaguchi-gumi is growing rapidly these days and makes up almost half of the whole yakuza population," says Kohei Kishi, who leads the Organised Crime Department.
"It has a great influence on other yakuza groups. Unless we crush Yamaguchi-gumi we cannot hit the whole yakuza world. So we are concentrating on crushing the Yamaguchi-gumi."
Sumo's governing body has been trying to restore the confidence of fans by announcing that ties to organised crime will not be tolerated.
The yakuza are no longer welcome at tournaments - and surveillance cameras are being used to try to keep them out of the audience.
But the damage to Japan's national sport has been done.
"The sumo scandal is one battle in the National Police Agency's war on organised crime," says Jake Adelstein. "It's a war, so there are going to be casualties, and sumo is going to be a casualty."