Up to 40 wrestlers may involved in bout fixing in the traditional Japanese sport of Sumo.
Allegations against 14 mid-ranked wrestlers arose last month during a police probe into illegal betting on baseball matches.
Now one of the 14 accused has allegedly told investigators that he knew of about 40 wrestlers who were involved in fixing results according to a Japanese newspaper.
Fighter-turned-stablemaster Takenawa was one of three people who had admitted trading wins, a practice that allows wrestlers to avoid a drop in their ranking and the accompanying large salary cut.
The fixing of sumo bouts is not illegal in Japan and betting is outlawed in Japan except on horse racing and some motor sports.
Sumo, an ancient and highly ritualistic sport, has been shaken by a series of scandals in recent years, including illegal drug use and brutal training methods that resulted in the death of a teenaged apprentice.