Comment on Two sumo wrestlers walked into a bar. The brawl they had is rocking Japan’s sumo world.

TOKYO — The world of sumo has been turned upside down like, well, like a wrestler pushed from the ring. In a case that has enthralled Japan and dominated the headlines for a week, a 33-year-old grand sumo champion, a Mongolian called Harumafuji, is accused of assaulting a younger wrestler, a 27-year-old Mongolian called Takanoiwa, with items possibly including a beer bottle, an ice pick, an ashtray, a microphone and a karaoke remote control. Harumafuji, who holds the top rank of yokozuna, says he used only his bare hands, and a contentious investigation is now going on.