Relegation-threatened Burnley have sacked manager Sean Dyche.
The decision comes with the Clarets 18th in the Premier League, four points adrift of safety having won only four matches all season.
A statement said: "Burnley Football Club can confirm the Club has parted company with manager Sean Dyche, assistant manager Ian Woan, first-team coach Steve Stone and goalkeeping coach Billy Mercer."
The 50-year-old, who signed a new contract due to run until the summer of 2025 in September, had been the longest-serving manager of any club in the Premier League, having taken charge in October 2012.
During that time he had twice led the Clarets to promotion and brought European football to Turf Moor in 2018 despite a limited budget, but his side have been in the bottom three virtually all season and last week's 2-0 defeat at Norwich was seen as a major setback in their survival bid.
Chairman Alan Pace said: "Firstly, we would like to place on record our sincere thanks to Sean and his staff for their achievements at the club over the last decade.
"During his time at Turf Moor, Sean has been a credit both on and off the pitch, respected by players, staff, supporters, and the wider football community.
"However, results this season have been disappointing and, while this was an incredibly difficult decision, with eight crucial games of the campaign remaining, we feel a change is needed to give the squad the best possible chance of retaining its Premier League status."
Given that defeat was five days ago, the timing of the announcement a little over 48 hours before Sunday's match at West Ham comes as a surprise.
Though Dyche's side have conceded the second fewest goals in the bottom half of the Premier League, they have scored only 25 times in 30 league matches this season.
Summer signing Maxwel Cornet, who missed a glorious chance when Burnley were 1-0 down at Carrow Road, has struggled with fitness at times, while Wout Weghorst, brought in to cover for the unexpected loss of Chris Wood to Newcastle in January, has only one goal in 12 appearances.
In his statement, Pace said that club captain Ben Mee, 32, will form part of the coaching staff for Sunday's trip to West Ham.
"Under-23s coach Mike Jackson, assisted by academy director Paul Jenkins, Under-23s goalkeeping coach Connor King and club captain Ben Mee have been asked to take charge of the team for Sunday's game with West Ham United," Pace said.
"The process of replacing Sean has begun and further announcements will be made to supporters in due course."
A press conference scheduled to take place on Friday to preview the West Ham match was cancelled but Hammers' boss David Moyes expressed his surprise at the decision to sake Dyche.
Moyes said: "I'm shocked and a little bit surprised as well. I think Sean's done such a great job and established Burnley in the Premier League over many years.
"Over recent times Burnley have been a very difficult team to play against and most of that has been done by Sean."