Liam Rosenior was sacked as Chelsea manager after less than four months in charge on Wednesday following a run of five successive Premier League defeats.
Beaten seven times in their last eight games in all competitions, Chelsea have failed to even score while losing five consecutive league games for the first time since 1912.
The 41-year-old had been lured away from Strasbourg, the French club which is affiliated to Chelsea's American owners, in January following the departure of Enzo Maresca.
But a 3-0 defeat to Brighton on Tuesday that Rosenior himself labelled "unacceptable" proved to be the final straw for the Blues' hierarchy.
"Chelsea Football Club has today parted company with Head Coach Liam Rosenior," read a club statement.
"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," the statement added.
Calum McFarlane, who was Rosenior's assistant, will take charge as a caretaker for the rest of the season, with his first match the FA Cup semifinal against Leeds United on Sunday.
Chelsea sit seventh in the Premier League, seven points adrift of the Champions League places, with four games of the season remaining.
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STAGGERING LOSSES
MacFarlane will be tasked with salvaging at least some form of European football to ease the financial burden on a club that posted a staggering £262.4 million pre-tax loss last season.
Chelsea added they will "undertake a process of self-reflection to make the right long-term appointment".
Rosenior was a surprise choice to replace Italian coach Maresca, who was considered to be popular with the Chelsea players but had fallen out with his superiors.
After promising early signs, Chelsea were knocked out of the League Cup by Arsenal and were then humiliated 8-2 on aggregate by Paris Saint-Germain in the Champions League last 16.
Cracks in the relationship between the squad and coach have been in evidence for weeks.
The decision to part company with Maresca in January was publicly questioned by Enzo Fernandez and Marc Cucurella.
Fernandez was then dropped for two games for suggesting he would be open to a summer move to Real Madrid and was forced to apologise.
Rosenior's frustration was clear after the defeat to Brighton.
"I have defended the players at times when it was the correct thing but I can't defend that performance. It doesn't represent this football club, it doesn't represent anything I ask from the group and that has to change," the Englishman said, adding: "I feel numb I'm so angry."
Chelsea won the World Club Cup and the UEFA Conference League last year, but have little else to show for well over one billion pounds of spending on players since a US consortium took over following Roman Abramovich's trophy-laden ownership of the club.
Fans have continuously protested against the club's owners BlueCo, who have embarked on a scattergun approach to hoovering up young talent from across the globe.
That policy has secured some notable successes such as Cole Palmer.
But the England international is among the star names in the squad who could also move on at the end of the season as Chelsea face up to a second season in three years outside the Champions League.