Aston Villa have confirmed the departure of Gerard Houllier as manager after only nine months in charge.
The 63-year-old Frenchman missed the final month of the season because of heart problems.
He had been expected to leave his post after undergoing tests this week.
Doctors advised that he will require further time to recuperate and Villa officials were said to be concerned a return to the dugout could cause further health issues.
In a statement, Houllier, who left his role as technical director at the France Football Federation (FFF) to take over at Villa, did not rule out the possibility of returning to the game.
He said: "I am extremely disappointed that I will not have the opportunity to manage Aston Villa next season."
We take a look at the managers in contention for the Villa hot-seat: