A 3-0 defeat to Juventus on Tuesday has cost Roberto Di Matteo his job at Champions League holders Chelsea.
The Italian, only appointed in March 2012, has been sacked on Wednesday morning despite winning the FA Cup and Champions League last season.
“Chelsea Football Club has parted company this morning with Manager Roberto Di Matteo,” a statement read.
“The team's recent performances and results have not been good enough and the owner and the Board felt that a change was necessary now to keep the club moving in the right direction as we head into a vitally important part of the season.
“The club faces a difficult task ahead in qualifying for the knockout stages of the UEFA Champions League as well as maintaining a strong challenge for the top of the Premier League while competing in three other cup competitions. Our aim is to remain as competitive as possible and challenge strongly on all fronts.
“The owner and the Board would like to thank Roberto for all he has done for the club since taking over in March. Roberto helped guide us to an historic Champions League victory and a seventh FA Cup. We will never forget the huge contribution he has made to this club's history and he will always be welcome at Stamford Bridge.
“The club will be making an announcement shortly regarding a new first team manager.”
Chelsea will need to beat Nordsjaelland and will require Juventus to lose at Shakhtar Donetsk to reach the last 16 of the Champions League.
Chelsea are third in the Premiership, four points behind Manchester City.