John Terry is struggling to comprehend the prospect of Chelsea not being in next season's Champions League and admits he and his team-mates need to "man up" to get there.
The Blues are in real danger of finishing outside the Barclays Premier League top four, while recent form suggests they are not equipped to win the European Cup.
That would herald their worst season since Roman Abramovich took over the club and captain Terry revealed he is losing sleep over the prospect of Tottenham and Manchester City finishing above his side.
"That's obviously the worst thing to think about, looking at Spurs and City," he said.
"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. We have to man up a little bit as a group of players and take responsibility."
He added: "It's even hard to get my head around it now.
"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."
The Blues hit a new low in the Abramovich era on Saturday when they crashed out of the FA Cup against Everton, having already all but surrendered their Premier League title.
That has piled the pressure on manager Carlo 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 insists it has been the players who have "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. 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."
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