Roy Keane will once again link up with Martin O'Neill to become Nottingham Forest assistant manager, the Sky Bet Championship club have announced.
The 47-year-old was O'Neill's right-hand man during their 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 after making over 100 appearances for the club between 1990 and 1993 before moving to Manchester United, where he went on to win seven Premier League titles.
It was widely expected that Keane would join as assistant to O'Neill, who became the club's 11th full-time boss since 2011 two weeks ago, and Forest confirmed his arrival today.
Keane said: "I am happy to be back. When Martin got the job and gave me a shout, I thought that once a few things fell into place I'd be ready for it.
"It is good to be back and it will probably take a couple of days to get back in the swing of things. Obviously, I had great memories of my career here as a player, the club gave me my chance and I will always remember them for that.
"But it is a different challenge now and I am in a different position coaching the players. I am looking forward to it, a huge challenge ahead and 20 years out of the Premier League. It will be tough but I am looking forward to it.
"We will give it a good go, I have huge respect for Martin and the club and it fell into place nicely. I have seen the team a number of times over the last year or two and it is going to be tough but hopefully, with one or two signings, a bit of luck we can hopefully be competing."
Keane guided Sunderland back to the Premier League during his first season in charge at the Stadium of Light in 2006 before resigning in December 2008 and went on to manage Ipswich from 2009 to 2011 before joining O'Neill at Ireland in 2013.