London - Roy Keane will once again link up with Martin O'Neill to become Nottingham Forest assistant manager, the Championship club announced on Monday.
The 47-year-old was part of the backroom staff during O'Neill's five-year spell in charge of the Republic of Ireland between 2013 and 2018.
Keane, like O'Neill, is a favourite at the City Ground, He made more than 100 appearances for the club between 1990 and 1993 before moving to Manchester United, where he won seven Premier League titles.
"Nottingham Forest are delighted to confirm that former Red Roy Keane has returned to the club as assistant manager," the club said on its website.
"Keane, who started his professional football career with the Reds in 1990 and went on to make over 100 appearances... joins Martin O'Neill's backroom staff with immediate effect."
The Irishman has previously managed Sunderland and Ipswich Town.
O'Neill and Keane took Ireland to Euro 2016, where they reached the round of 16.
O'Neill, who won two European Cups at the City Ground in his playing days, was appointed as manager earlier this month, replacing Aitor Karanka.