As the gravity of yokozuna Harumafuji's assault further emerged Wednesday, condemnation of his behavior has morphed into disappointment that sumo's veiled underbelly has yet again stained the reputation of Japan's national sport.

The latest blow to the ancient sport came just as it had begun to regain lost popularity with the promise of fierce competition between the four top-division yokozuna leading to a string of sellout tournaments.

Despite his bid for a 10th career title, Harumafuji withdrew from the ongoing Kyushu Grand Sumo Tournament after it was revealed he was involved in a drunken brawl late last month which left fellow Mongolian sumo Takanoiwa with serious injuries.

According to sources familiar with the matter, the brawl broke out when a group of Mongolian wrestlers gathered over drinks during the autumn regional tour in Tottori. Harumafuji, angered that Takanoiwa tried to answer his phone while being berated, smashed a beer bottle over the lower-ranked wrestler's head.

When Takanoiwa fell, the intoxicated grand champion continued to rain blows down on the bleeding wrestler.

Two other grand champions, Hakuho and Kakuryu, were also present while Terunofuji, Harumafuji's Isegahama stablemate, ended up taking a few punches amid the chaos.

"It happened so fast none of us realized what the loud smashing sound was. (Harumafuji) continued with 20 to 30 punches with his bare hands. Takanoiwa was defending himself with both hands as he was hit," an unnamed source who was at the party said.

The eighth-ranked maegashira Takanoiwa was diagnosed with a concussion, a fracture at the base of his skull and a cerebrospinal fluid leak among other injuries, and was hospitalized from Nov. 5 to 9.

The scandal was the latest controversy to hit sumo after a series of hazing, match-fixing and violent incidents had brought shame upon the highly-regarded sport.

A high-profile 2007 case saw 17-year-old wrestler Tokitaizan, whose real name was Takashi Saito, die after he was beaten by his stablemaster and three older wrestlers after attempting to flee from the Tokitsukaze stable. All three assailants were eventually arrested.

In an interview with Kyodo News on Tuesday, the murdered wrestler's father Masato Saito said even 10 years after his son's death, he still gets chills when he watches sumo on TV as it reminds him of his son's bruised and battered body.

Saito, who has been ill due to stress, says he is told by friends to put the past behind him, but he feels like his life froze when his son died. He says he has every excuse for withdrawing, but the sport's governing body cannot do the same.

"I'm truly angered by the fact that nothing has changed in the world of sumo," Saito said.

"What did Takashi's death mean? The Japan Sumo Association only offers a stopgap solution and they're easy on their own people. Its structure is still that way. All those times I dragged myself to the courthouse, and nothing has changed. It's pathetic," he said.

As the abuse scandal involving the 33-year-old wrestler from Ulan Bator was exposed, igniting outrage across the country, public figures were quick to voice their opinions on sumo's ills.

"Sumo is a sport that is of great interest to our citizens. They expect wrestlers to understand the weight of tradition they carry outside of the ring and devote themselves to training," Chief Cabinet Secretary Yoshihide Suga said.

Meanwhile, Harumafuji's stablemaster refused to speak to the crowd of reporters that waited for him at Fukuoka Kokusai Center, the Kyushu tournament venue.

The JSA, whose failure to address the serious incident will likely be interpreted by the public as a cover-up attempt, said its crisis management team will look into the case, while the Tottori prefectural police have launched an investigation.

Although the JSA said it will not hand down a ruling until after the Nov. 12-26 tournament, speculation has hit a fever pitch that a disgraced Harumafuji will retire.