Mongolian grand champion Hakuho maintained his sole lead after beating former ozeki Kotoshogiku on Monday, the ninth day of the New Year Grand Sumo Tournament.

The 33-year-old Hakuho, the only yokozuna in action, beat Kotoshogiku to keep a perfect record at the 15-day meet at Tokyo's Ryogoku Kokugikan. He remains on course to extend his record number of makuuchi top-division championships to 42.

After slapping Kotoshogiku's face following the initial charge, the Mongolian yokozuna grabbed the 173-kilogram maegashira by the belt and thrusted him down. It was Hakuho's 56th win over Kotoshogiku (4-5) in 62 bouts.

Rank-and-filer Chiyonokuni is alone in second place, trailing Hakuho by one win, while two ozeki, competing at sumo's second-highest rank, lost their respective matches and fell further behind.

Takayasu dropped to 4-5 after losing to sekiwake Tamawashi (7-2), while fellow ozeki Goeido was unable to resist powerful shoves by No. 4 Okinoumi (6-3) and suffered his sixth loss.

The January tournament is missing a number of fan favorites due to injuries. The other grand champion, Kakuryu, pulled out after going 2-3, and ozeki Tochinoshin withdrew without winning a single bout.

But the biggest story at the first grand tournament of the year has been the retirement of injury-plagued yokozuna Kisenosato from the sport. The Japanese-born grand champion opened the tournament with three straight losses before announcing his retirement last Wednesday.

No. 15 maegashira Chiyonokuni survived a scare against No. 12 Meisei (6-3) to keep his hopes for his first Emperor's Cup alive. Meisei attempted to flip Chiyonokuni down at the edge of the ring, but Chiyonokuni resisted and slapped his opponent straight down to the sandy surface.

With the victory, the Kokonoe stable wrestler secured his first winning record since finishing 12-3 at the Summer tournament in May.

"I'm glad. I think I did really well," said Chiyonokuni, who sustained a left-elbow injury in July. "My body doesn't hurt and I'm confident I'm wrestling well. I'm only focused on each of my bouts."

In one of the day's shortest bout, Takakeisho pushed out No. 2 Nishikigi (4-5) in just 3.1 seconds. At 7-2, the newly-promoted sekiwake remains in contention for his second straight championship following his victory at the November tourney in Fukuoka.

The two other wrestlers -- No. 8 Kaisei and No. 13 Yago -- who started the day at 7-1, suffered losses and fell into a four-way tie for third.

Brazilian wrestler Kaisei was defeated by No. 7 Ryuden (3-6), while Yago was unable to keep his winning streak going in his makuuchi debut tournament after losing to No. 11 Ikioi (5-4).