Liam Rosenior has been sacked by Chelsea following a run of five consecutive Premier League defeats in which the team failed to score.
The former Hull and Strasbourg boss signed a six-and-a-half-year deal in January and started brightly but the team have plummeted down the table and are almost certain to miss out on qualification for the Champions League.
They were beaten comfortably 3-0 by Brighton at the Amex Stadium on Tuesday, widely considered to have been the team's worst performance of the season.
Calum McFarlane will take charge until the end of the season, starting with Sunday’s FA Cup semi-final against Leeds.
A club statement read: "Chelsea Football Club has today parted company with Head Coach Liam Rosenior.
"On behalf of everyone at Chelsea FC, we would like to place on record our gratitude to Liam and his staff for all their efforts during their time with the Club.
"Liam has always conducted himself with the highest integrity and professionalism following his appointment midway through the season.
"This has not been a decision the Club has taken lightly, however recent results and performances have fallen below the necessary standards with still so much more to play for this season. Everyone at Chelsea FC wishes Liam every success in the future.
"Calum McFarlane will take charge of the team as Interim Head Coach until the end of the season with support from existing Club backroom staff, as we strive to achieve European qualification and progress in the FA Cup.
"As the Club works to bring stability to the Head Coach position, we will undertake a process of self-reflection to make the right long-term appointment."
The first-team squad were informed on Wednesday prior to the decision being made public.
McFarlane, who led the team for two matches following the departure of Enzo Maresca in January, will begin his period in temporary charge with Sunday's FA Cup semi-final against Leeds.
Chelsea’s collapse under Rosenior began with a 5-2 hammering away to Paris St Germain on 11 March and from there the rot set in.
The team has since plummeted down the league table, having not picked up a point since beating Aston Villa on 4 March, and they were beaten comfortably at the Amex Stadium on Tuesday in what was widely considered to have been their worst performance of the season.
During the match, Rosenior was for the first time subjected directly to chants from supporters calling for him to leave, while there were also the now-customary demands for owners BlueCo to sell up.
PA understands the decision to dismiss the 41-year-old was based on results and performances and was not connected to a breakdown in relationships.
The belief internally was that with European qualification still on the line and with the club still involved in the FA Cup, action had to be taken to prevent the season from unravelling further.
It was acknowledged that Rosenior was placed in a difficult position in coming into the job in January, and the owners and sporting directors were planning to review his position at the end of next season following a full campaign.
However, it was clear during Tuesday’s defeat on the south coast that his position had become untenable, and despite there being those within the club who were desperate for him to succeed, his tenure was ended after only 23 matches.
Listen to the RTÉ Soccer podcast on Apple Podcasts, Spotify or wherever you get your podcasts.
Watch Arsenal v Lyon in the UEFA Women's Champions League on Sunday from 3pm on RTÉ One and RTÉ Player
