Lisburn Distillery manager John Cunningham has left his position 'by mutual consent' three days after the club secured their Premiership status.
Cunningham took over at New Grosvenor after previous boss Tommy Wright resigned to become part of Stephen Lomas' backroom team at St Johnstone.
"We sat down with John and we both felt that a change was required," said the club's chairman Jim Greer on Monday.
"John has worked tirelessly and introduced new players to the club."
"He has been a great servant of this club since he joined us as assistant manager in September 2009, during what were often difficult times.
"We thank him sincerely for all his hard work during his time with us.
"When he was appointed manager in November 2011, his appointment was to the end of the current season and we agreed we would then review the position.
"We wish John every success for the future, he will be always be assured of a warm welcome at New Grosvenor."
"The board will now consider how the club will go forward in terms of a new manager and the playing structure at the club."
The Whites beat Newry City 3-2 on aggregate in last week's promotion/relegation play-off.
Cunningham previously managed both Institute and Dungannon Swifts in the top flight.