Martin O'Neill (left) and Roy Keane spent five years together at the Republic of Ireland, before reuniting at Nottingham Forest in January
Nottingham Forest assistant manager Roy Keane has left the Championship club.
The 47-year-old former Forest player returned to the City Ground in January following the appointment of Martin O'Neill, with whom he worked at the Republic of Ireland.
The ex-Manchester United midfielder described the experience of working with O'Neill as "one of my greatest in football, both as a player and coach".
Forest finished ninth in the table in 2018-19.
Keane had spells as manager of Sunderland and Ipswich Town before being part of the Republic of Ireland set-up when they reached the last 16 of the 2016 European Championship.
As a player, he appeared in FA Cup and League Cup finals for Forest after joining from Irish club Cobh Ramblers in 1990.
He later won seven Premier League titles, four FA Cups and a Champions League during more than a decade at Old Trafford.
Nottingham Forest begin their Championship campaign at home to Slaven Bilic's West Bromwich Albion on Saturday, 3 August.