Houllier has been absent from the Villa dugout since undergoing heart surgery following chest pains he suffered in April.
McGregor, who will cost around £5 million, will replace Brad Friedel, who is set to leave this summer.
Houllier has been absent from the Villa dugout since undergoing heart surgery following chest pains he suffered in April.
McGregor, who will cost around £5 million, will replace Brad Friedel, who is set to leave this summer.
