Yokozuna Terunofuji will skip the Autumn Grand Sumo Tournament due to a nagging back injury, his stable said Friday, leaving the 15-day competition without a wrestler at the sport's highest rank.

The tournament, opening Sunday at Tokyo's Ryogoku Kokugikan, will be the second meet in a row that sumo's sole yokozuna has missed because of lumbar disc herniation and other concerns.

The 31-year-old Terunofuji, who was forced out of action on Day 4 of the July tournament, has been unable to train without pain.

His stablemaster Isegahama said the Mongolian-born yokozuna decided to skip the September meet on Thursday.

"His back is not good. Even after going to hospital, he was not in any condition to resume sumo," Isegahama said, adding they were "not at the stage" of deciding on surgery. "If the pain doesn't go away, we'll discuss taking the next step."

After undergoing double knee surgery in October last year and missing three straight competitions, Terunofuji made a triumphant return at this year's May tournament, where he won his first championship in a year with a 14-1 record.

But the new injury will see the eight-time Emperor's Cup winner withdraw from a seventh tournament out of 13 since his debut at sumo's highest rank in September 2021.

Terunofuji's absence leaves a trio of ozeki — Kirishima, Takakeisho and newly promoted Hoshoryu — as the highest-ranked wrestlers at the upcoming tournament.