John Terry insists Chelsea's players are 100% behind Carlo Ancelotti and ordered them to "man up" and prove it by rescuing the club's season.
The Blues hit a new low in the Roman Abramovich era on Saturday when they crashed out of the FA Cup, having already all but surrendered their Premier League title.
That piled the pressure on Ancelotti ahead of Tuesday night's Champions League last-16 first leg at FC Copenhagen, when the last silverware Chelsea can win this season will be on the line.
Defeat to the lowest-ranked team left in the competition could test billionaire owner Abramovich's patience to breaking point, but captain Terry on Monday night insisted it had been the players who had "underachieved".
"The players are 100% behind the manager," he added.
"He's got total confidence in us, and that will remain the same.
"We believe in the manager and the players."
Ancelotti was twice backed by Abramovich at the end of 2010 following Chelsea's worst run in the league for almost 15 years.
A mini-revival followed but the past fortnight has witnessed another calamitous run of results that sees them in real danger of failing to qualify for next season's Champions League.
England defender Terry said: "It's been difficult, because at times we have shown our quality.
"The Sunderland game I thought possibly was the turning point, going a goal down and showing the character to come back and win.
"If we could've beaten Liverpool, we could have maybe gone on a good run and sorted ourselves out a little bit.
"But we are where we are - we have to deal with that.
"We have to man up a little bit as a group of players and take responsibility."
Admitting he had lost sleep during the current malaise, he added: "It's down to myself as captain, Lamps (Frank Lampard) and Didier (Drogba) - as well as the rest of the squad who have a responsibility - to look at their own form, their own characters and just make sure we stay together.
"We've always come out the other end."
Lampard declared last week it would be a "disaster" if Chelsea failed to overhaul Tottenham or Manchester City and finish in the Premier League top four.
Terry concurred, saying: "That's obviously the worst thing to think about, looking at Spurs and City.
"They're playing well and picking up points at a crucial time.
"That would be disastrous for the football club if we don't qualify for the Champions League.
"It's even hard to get my head around it now."
He added: "That's what we've still got at the football club, hunger and desire.
"We missed out on the Premier League for three years when Man United won it, and it hurt.
"That's what I lose sleep over, watching other teams lift trophies, because I want to be the one lifting trophies for this football club."
Speculation about the reasons behind Chelsea's slump has been rife, with some claiming the team is past its sell-by date.
Terry, 30, scoffed: "We went through a bad spell in the Premier League last year.
"You get the speculation, you get the people saying the squad is past its best, we're getting too old - and then we go on and win the double.
"No-one comes out and apologises for the statements they made.
"We're a year older, and next year we're going to be another year older.
"That doesn't take away the quality we have.
"The manager has brought in two very good young players as well - we're talking world-class players - in Fernando (Torres) and David (Luiz)."
Terry also rubbished suggestions November's controversial sacking of Ray Wilkins had been the catalyst for the club's downturn but admitted the former Chelsea captain was missed.
"He was obviously a massive asset to this club and brought an awful lot," Terry said.
"We can look at that and say, 'Yeah, we've missed him', but we knew we had to get on with it.
"We've spoken to Ray in the meantime.
"He's still in a good relationship with the players and the manager."
Terry even managed to put a positive spin on Chelsea having flopped in the league and FA Cup.
"That could be a blessing in disguise," he said, insisting the Champions League was the one he really wants.
"It's the one that's eluded the football club and myself as a player.
"So we aim to go to Wembley and hopefully lift this trophy."
