The former Wimbledon striker famed for a lack of hair,managed City's reserve team last season and assisted Micky Adams on a match day.
No news has been forthcoming regarding who will take over as reserve team boss. However, fitness coach Darren Robinson who took the team for the final game of last season at Southampton is a likely candidate,if Adams opts not to recruit another member of staff.
On promoting Cork, the City boss said:" Alan's been with me throughout my career as a manager and he's more than capable of stepping into Adrian's shoes."