Upon the enthronement of Emperor Daigo, Tokihira and Michizane were appointed as Sayudaijin (Ministers of the Left and Right), however, Tokihira gradually came to oppose Michizane, and at last had him demoted to Dazaifu on false charges.
醍醐天皇が即位すると道真とともに左右大臣に並ぶが、次第に対立し道真を遂に讒言して大宰府へ左遷させた。