Frank Lampard has been sacked by Chelsea less than 24 hours after the club's FA Cup win over Luton Town.
The former Chelsea midfielder has paid the price for the club's poor form in the Premier League.
Chelsea go into Wednesday night's home game against Wolves in ninth place, 11 points off top spot and five off the Champions League places.
Lampard led Chelsea to a fourth-place finish in the league last season but the club spent more than 200 million euro in the transfer window and have already lost six league games this season.
A statement from the club read: "This has been a very difficult decision, and not one that the owner and the Board have taken lightly.
"We are grateful to Frank for what he has achieved in his time as Head Coach of the Club. However, recent results and performances have not met the Club’s expectations, leaving the Club mid-table without any clear path to sustained improvement.
"There can never be a good time to part ways with a club legend such as Frank, but after lengthy deliberation and consideration it was decided a change is needed now to give the Club time to improve performances and results this season."
Chelsea Football Club has today parted company with Head Coach Frank Lampard.
— Chelsea FC (@ChelseaFC) January 25, 2021
Chelsea owner Roman Abramovich added: "This was a very difficult decision for the Club, not least because I have an excellent personal relationship with Frank and I have the utmost respect for him.
"He is a man of great integrity and has the highest of work ethics. However, under current circumstances we believe it is best to change managers.
"On behalf of everyone at the Club, the Board and personally, I would like to thank Frank for his work as Head Coach and wish him every success in the future.
"He is an important icon of this great club and his status here remains undiminished. He will always be warmly welcomed back at Stamford Bridge."
Chelsea say they will be making no further comment until a new manager is appointed but former Borussia Dortmund and PSG boss Thomas Tuchel is expected to take the reigns at Stamford Bridge.