Mongolian yokozuna Hakuho outmuscled Kisenosato to preserve his unbeaten record, but Estonian ozeki Baruto suffered his second loss at the Summer Grand Sumo Tournament on Tuesday.
Looking for his 14th Emperor's Cup, Hakuho improved to 10-0 at the 15-day meet and extended his winning streak to 27 bouts dating back to the New Year basho in January.
Hakuho blasted out Kisenosato in the day's finale at Ryogoku Kokugikan after the sekiwake gave the lone yokozuna as good as he got. Kisenosato fell to 5-5.
In a battle between Bulgarian and Estonian giants, Kotooshu got a firm right-handed grip on fellow ozeki Baruto's belt before lifting the man mountain over the edge for a seventh win.
Baruto fell two wins behind Hakuho in his bid to become the second European wrestler after Kotooshu to win a title.
Hakuba, Aran and Shimotori won their respective bouts to join Baruto at 8-2.
Mongolian maegashira Hakuba yanked countryman Harumafuji down to the sandy surface, handing the ozeki his third loss of the tournament.
Veteran Kaio picked up his 997th career win by forcing out Kotomitsuki in another all-ozeki affair, leaving both men at 6-4.