Yokozuna Hakuho withdrew from the Autumn Grand Sumo Tournament on Tuesday, citing an injured left knee.
Hakuho, 30, injured his knee in pre-tournament sparring and lost his first two bouts of the 15-day basho. It is the first time the Mongolian yokozuna has pulled out of a major tournament since the 2006 Kyushu basho when he was still an ozeki.
"There is inflammation in my left knee, and I can't get any strength into it, so I decided to pull out," said Hakuho. "I can't stand in the ring with a halfhearted feeling. I want to apologize to everyone. But in my case, I have done many things, so please forgive me."
Hakuho, who has never missed a tournament since gaining promotion to sumo's top rank for the 2007 Nagoya Grand Sumo Tournament, will sit out his third overall meet.
His withdrawal also brings an end to the 722 consecutive days he has competed as a yokozuna — the longest in the history of the sport. Hakuho also saw his all-time record of posting consecutive double-digit wins end at 51 tournaments.
He forfeits Tuesday's match against Aoiyama.
Yokozuna Harumafuji is already sitting out the 15-day meet due to a troubled right elbow.