Yokozuna Kisenosato and ozeki Terunofuji have both pulled out of the Nagoya Grand Sumo Tournament due to injuries and will forfeit their sixth-day bouts, sumo officials said Friday.

The 31-year-old Kisenosato, who has been competing despite delayed recovery from an upper arm injury, injured his left ankle while losing to third-ranked maegashira Ikioi in Thursday's bout at Aichi Prefectural Gymnasium. He entered the meet with a perfect 15-0 head-to-head record against Ikioi.

Medical reports submitted to the Japan Sumo Association revealed he has been diagnosed with damaged ligaments in his left ankle joint and will need three weeks of treatment.

It is the second straight tournament that the grand champion from the Tagonoura stable has been forced to withdraw from, and the third time overall.

"He said he is no condition to wrestle. The pain in his left arm seems to be gone but he hasn't been able to put on good sumo. He was desperate and hoping to heal himself in the ring," his stablemaster Tagonoura said.

"It was a difficult decision. But we'll think of what's best going forward and make sure the fans will get to see a healthy yokozuna again."

Meanwhile, Terunofuji, who underwent endoscopic surgery on his left knee last month, also pulled out and will have to compete in the next Autumn Grand Sumo Tournament as a demotion-threatened "kadoban" if he misses the remainder of the Nagoya basho.

He was diagnosed with a left knee meniscal injury and his scheduled opponent for Friday, No. 1 maegashira Shodai, wins by forfeit, leaving Terunofuji at 1-5.

For the 25-year-old Mongolian ozeki from the Isegahama stable, it is the second time in his career he is withdrawing from a tournament.