Tochiazuma's brief run as the leader of the pack came to an end Thursday as sekiwake Kotomitsuki pulled the ozeki down to his first loss of the New Year Grand Sumo Tournament.
Kotomitsuki's 10th win of the tourney at Ryogoku Kokugikan kept the sekiwake's own title hopes alive while ozeki Chiyotaikai grabbed a share of the lead with Tochiazuma at 11-1 with a workmanlike win over Tosanoumi.
In the day's main event, Tochiazuma, who has not shaved during his 11-match winning streak, and Kotomitsuki, seeking to end a two-day losing skid, battled for more than a minute to gain the advantage on the belt.
Kotomitsuki (10-2) kept the pressure on Tochiazuma and finally saw his chance to send the newly promoted ozeki sprawling to the ring's sandy surface with a well-timed shove.
"I put out all the energy I had," said Kotomitsuki, who falls in a step behind the co-leaders in his own bid for the Emperor's Cup and possible promotion to ozeki.
Chiyotaikai, meanwhile, who appeared with bandages on both feet after stubbing his toe on the ring's surface Wednesday, overpowered No. 7 maegashira Tosanoumi (8-4) with an aggressive series of slaps before finally pulling the taller wrestler face-down to the ring.
Ozeki Musoyama (9-3) charged swiftly against Tochinonada (7-5) and denied the No. 6 maegashira an important eighth win by shoving him easily over the straw ridge.
In other bouts, Mongolian sekiwake Asashoryu (7-5) flipped over ozeki Kaio (8-4) while compatriot komusubi Kyokutenho (4-8) slapped down second-ranked maegashira Tamanoshima (2-10) for an encouraging win.
Top maegashira Kyokushuzan (5-7), a former komusubi himself, threw down current komusubi Wakanosato (6-6) as he battles to avoid relegation for the spring tourney in March.
American maegashira Sentoryu evened his record at 6-6 by slapping down 11th-ranked Tokitsuumi (8-4) in an early bout.