 Kōbō made his professional debut in March 1989 at the age of 15.He worked his way quickly through the lowest three divisions, making his "makushita" debut shortly after his 18th birthday, less than three years into his career.However, he was unable to advance further for several years, reaching "sekitori" status only in January 1999 upon promotion to the second highest "jūryō" division, after nearly ten years of toiling in the lower divisions.