Former Chelsea forward Gianfranco Zola has warned his ''fragile'' former team they are running out of time to turn around their stuttering season.
A 3-1 first-leg defeat to Napoli in the Champions League last-16 made it five games without a win for Andre Villas-Boas' side and left them with a huge task on their hands to avoid elimination from European competition.
They are also languishing fifth in the Premier League table and must come through a replay with Birmingham if they are to progress in the FA Cup.
And Zola said: ''I think they will have to analyse what is going on and to sort it out quickly.''
The club's poor run of results and performances have been characterised by defensive struggles, with the Blues failing to keep a single clean sheet in the absence of captain John Terry, who is expected to be sidelined for a further six weeks by a knee problem.
Zola continued: ''Especially psychologically, at the moment they are a little too fragile and you cannot afford that, especially at this stage of the season.
''You have to know what you're doing and you have to do it 100% convincingly.''
Meanwhile, Chelsea defender Gary Cahill said he had a Champions League debut night to forget.
Cahill said: ''I'm ridiculously disappointed. Disappointed with the result, the night, the Champions League debut. So it was a pretty low night for myself, actually.''
As on Cahill's Chelsea debut against Manchester United, his new side threw away a lead after Juan Mata netted what could still prove a crucial away goal. Basic mistake after basic mistake followed and Napoli were more than worthy of their two-goal cushion.
''It started off brilliantly,'' Cahill said. ''We were frustrating them early doors, they made a mistake and we got the goal. For some reason, it seemed really open after that instead of really solid.
''We should have shut the door, made everything really compact and gone in at half-time 1-0 up, but it wasn't to be. I think we were too easily cut open.''
Cahill claimed a soaking pitch saw players ''slipping all over the place''.
''But it's no excuse for simple, basic things,'' he added. ''The goals came for a lot of long balls, which is bread and butter for people like myself. If we were getting caught open it might be different, but it was bread and butter things that went wrong.
''They had good players all around the pitch, but I think we made their job a little bit easier. We are still in it. To score two goals at Stamford Bridge is by no means beyond the realms of possibility.
''The third goal killed us a little bit, but we need to pull our finger out in the next leg and put in a better performance.''
Chelsea have now gone five matches without a win and it is hard to see them turning the tie around unless they can stop the rot before the second leg in two weeks' time.
Cahill said: ''It's a sticky situation at the minute. I have come in right in the middle of it. As soon as we get results, I think it will turn the corner, but it's difficult times.''
Next up is Saturday's Premier League clash with the Bolton side Cahill left just over a month ago.
''It has come round pretty quickly,'' he said. ''It is going to be a weird situation knowing the lads and knowing how they play. But, if selected, we need to get a result and put in a better performance in that game, for sure.''