Roy Keane has stepped down as Nottingham Forest assistant boss to resurrect his managerial career.
The 47-year-old spent just five months at the City Ground, where he was working as Martin O'Neill's number two.
Keane has previously managed Sunderland and Ipswich Town and is now seeking a new job.
A statement from the club read: "Nottingham Forest can confirm that assistant manager Roy Keane has left the club.
"Roy would like to express his gratitude to the club's owner, board of directors, the staff, the players and in particular manager Martin O'Neill for the opportunity to return to the City Ground."
Keane has not held a senior management position since leaving Sunderland in 2011, having worked in an assistant capacity with Republic of Ireland, Aston Villa and Forest over the last six years.
But he has previously admitted he is keen on landing a top job and has taken the decision to end his association with O'Neill, whom he also worked alongside in the Irish coaching set-up.
"Working with Martin over the last few years has been a magnificent experience, one of my greatest in football both as a player and a coach and one I want to personally thank him for," Keane said in a statement.
Forest finished ninth in the Championship last season, eight points adrift of the play-offs.