Birmingham City manager Tony Mowbray (60) is temporarily stepping away from the job for six to eight weeks to receive medical treatment, the Championship club said on Monday.
Mowbray took over in January after the sacking of former England striker Wayne Rooney, and his assistant Mark Venus will now take charge until his return.
"Following my recent LMA Health Assessment I have received a medical diagnosis that will require me to receive treatment," Mowbray said in a statement.
"Undergoing treatment will necessitate that I temporarily step away from the Technical Area as Manager of Birmingham City Football Club. The Club has been incredibly supportive of me and my family and we are very grateful."
Birmingham are 15th in the Championship and play at Ipswich Town on Saturday.