Tochinoshin maintained his perfect record and lead Thursday with a breakthrough victory over yokozuna Hakuho on Day 12 of the Summer Grand Sumo Tournament.

The Georgian-born sekiwake came into the final bout of the day at Ryogoku Kokugikan without a single win in 25 previous attempts against the all-time championship record-holder.

After a false start from Hakuho, the pair locked up in the center of the ring, each gripping the other's belt with nearly identical holds.

"I had a solid grip," Tochinoshin said.

Hakuho was justifiably downcast. "A loss is a loss," he said. "It was as you saw."

With the two powerfully built wrestlers holding each other in a stalemate, it was Tochinoshin who was able to dislodge his opponent's foothold before pushing him to the straw. As Hakuho dug in his heels, Tochinoshin mustered the strength for a final drive to force the grand champion over the straw bales.

The loss dropped Hakuho to 10-2 and into third place at the 15-day tournament. Fellow Mongolian grand champion Kakuryu (11-1) took sole possession of second place following his win over Ikioi (8-4) in the penultimate bout of the day.

(Tochinoshin, front, forces Hakuho over the straw bales)

The yokozuna needed nimble footwork to overcome the aggressive No. 5 maegashira, who secured a winning record the previous day.

The lower-ranked wrestler took the offensive from the outset as he sought to grab hold of the grand champion. Kakuryu backpedaled while slapping at Ikioi before pouncing on an opening for a push-out victory.

Komusubi Mitakeumi (7-4) hit a speedbump in his bid to regain sekiwake status in the form of No. 4 Chiyotairyu (5-7). The lower-ranked wrestler opened the bout with a shoulder blast that knocked his opponent backward and left him vulnerable to a quick push out.

Popular komusubi Endo (3-7-2) succumbed to No. 1 Kaisei (4-8) in his third straight loss since returning to the tournament after a two-match injury layoff.

Endo started the match on the front foot, driving Kaisei backward until the 204-kilogram Brazilian dug in at the edge of the straw. As Endo tried to force him out, Kaisei leveraged his 52-kg weight advantage to twist his opponent to the clay.

No. 5 Kotoshogiku (7-5) forced out Ichinojo (7-5) to move within one victory of a winning record for the tournament. The former ozeki resisted an attempted throw by the 224-kg Mongolian sekiwake before driving him backward over the straw.

On Friday, No. 4 Shodai will look for his eighth win, but will have to get past Tochinoshin to do it.

"I don't want to let him get hold of my belt," said Shodai of Tochinoshin, against whom he holds a 3-5 career record. "He's hot right now, so I want to avoid thinking weird things."

(Hakuho, left, and Tochinoshin after their bout)