Last-place Omiya Ardija fired manager Hiroki Shibuya and promoted assistant Akira Ito in his place, the J. League first-division side announced on Sunday.
Shibuya is the second coaching casualty in J1 this season. Albirex Niigata replaced Fumitake Miura with Wagner Lopes earlier this month.
On Saturday, Omiya lost 4-1 away to Kashiwa Reysol, its 10th defeat from 13 games. Ardija started the campaign with six straight losses and are deep in the relegation zone, five points away from safety.
Shibuya led Omiya to a club record fifth-place finish in 2016, but an exodus of core players such as current Kawasaki Frontale midfielder Akihiro Ienaga has hurt them.
Ardija have scored just seven goals this season.