Kisenosato crashed to a second defeat at the Summer Grand Sumo Tournament after the yokozuna was upset by top-ranked maegashira Endo on the fourth day of action on Wednesday.
Kisenosato, who is aiming for a third straight title, was made to pay for not finishing Endo off at Ryogoku Kokugikan and dropped two wins off the pace.
Fellow yokozuna Hakuho and Harumafuji both won to share the lead along with sekiwake Takayasu at 4-0 at the 15-day meet, but yokozuna Kakuryu fluffed his lines again and dropped to 1-3.