NAGOYA, Japan » The Nagoya Grand Sumo Tournament opened under a cloud of controversy yesterday as Japan’s national sport grapples with a widespread betting scandal.

With no live TV coverage and many fans opting to stay away in disgust, sumo wrestlers filed into Aichi Prefectural Gymnasium for yesterday’s bouts just days after police searched training facilities seeking more evidence in the latest scandal to tarnish the image of Japan’s ancient sport.

Dozens of sumo’s top wrestlers and coaches allegedly wagered as much as $50,000 on professional baseball games, with gangsters reportedly acting as go-betweens.

The Japan Sumo Association considered canceling the tournament because of the scandal but decided to go ahead as scheduled.

Security cameras were installed at arena gates in an effort to keep gangsters from entering the venue. Japan’s public TV broadcaster NHK is not airing live broadcasts of the tournament in response to viewer anger over the scandal.

The JSA is offering refunds on tickets bought for the tournament and decided the coveted Emperor’s Cup will not be awarded to the winner of the 15-day meet.

The current scandal has deepened concerns that the sport has closer ties to organized crime than it is willing to admit. Allegations of bout-fixing at the behest of gangsters have been frequently raised in Japan’s tabloid media, but the sumo association has repeatedly denied that.

In May, two sumo coaches were demoted for providing ringside seats to members of a notorious crime syndicate. The gangsters were allegedly seeking the front-row seats so that they would be visible in televised footage, allowing imprisoned fellow gang members to see them.

Senior wrestler Kotomitsuki and his coach, Otake, have been banned from the sport after the two revealed they had gambled on baseball. Police are investigating other wrestlers and more expulsions are possible.

An internal survey by the JSA last month found at least 65 of its members had been involved in illegal gambling.