Kenny Shiels has been sacked as manager of Derry City after the club's eighth-place finish in the 10-team League of Ireland Premier Division.
The move follows Friday's 5-0 drubbing away to St Patrick's Athletic which was Derry's 17th defeat in the last 23 league fixtures.
In September Shiels, 62, guided Derry to their first trophy success for six years as they lifted the EA Sports Cup.
But they ended the season by losing eight out of nine in the league.
In a brief statement on the club's website on Saturday, chairman Philip O'Doherty said: "Derry City and Kenny Shiels have decided to part company as of today.
"We acknowledge Kenny's contribution to the football club over the past three seasons, one of which was particularly difficult.
"We wish Kenny the best for the future.
"The club will make no further comment."
Chairman O'Doherty's mention of a particularly difficult season was a reference to the sudden death of club captain Ryan McBride in March 2017.
Shiels, who was in charge of Kilmarnock when they won the Scottish League Cup in 2012, succeeded Peter Hutton at the Brandywell in November 2015.
The Magherafelt man secured European football in the first two of his three seasons and last year signed a new contract which would have taken him up to 2019.
In an interview after Friday's defeat by St Pat's in Dublin, Shiels looked back on what he called 'a difficult season'.
"When we were going well, the media were very responsive and co-operative, and the city was as well.
"But when it is going bad, it is the complete opposite. There has been a complete lack of understanding."