Jose Mourinho has warned his Chelsea stars he won't tolerate a repeat of their Champions League flop when the Blues host Southampton on Sunday.
Mourinho was disappointed by his team's lacklustre effort in a 1-0 defeat against Basel on Tuesday and promised changes ahead of an important clash against the Saints, who would move above third-placed Chelsea in the Premier League table with a victory at Stamford Bridge.
"I never tolerate it but I have to live with it," Mourinho said of his side's low energy levels in Switzerland.
"It's football. Especially in teams in the building process, not the end product, not a team with years and years of work together or with maturity enough to keep that stability match after match.
"But I didn't like the performance, of course not. And we will try everything not to repeat. The good thing in the Champions League is that, when we felt the pressure, we always reacted and performed.
"When we responded to the first defeat, starting the matches in Bucharest and against Schalke, we were under pressure and knew if we made a mistake we'd be in big trouble, and at that moment the team reacted and played very seriously.
"Probably, in this game, because we felt the situation was under control, added with some fatigue -- I could easily identify that -- we had a bad performance.
"Hopefully on Sunday we will be ready because, in this moment, our situation is fine."
Chelsea are four points behind leaders Arsenal and by the time Mourinho's men kick-off on Sunday that gap will have stretched to seven if the Gunners beat Cardiff 24 hours earlier.
Mourinho has no intention of panicking just yet, though, and he believes Chelsea are still in a strong position to challenge for silverware on all fronts.
"We are a close distance to Arsenal, we are qualified for the last 16 in the Champions League and we will play the League Cup quarter-final," Mourinho said.
"We have to improve stability in our game, we have to improve aspects. Of course we have to. We also have to improve individually, especially with the younger players, but we are OK."
Spain's Fernando Torres is expected to replace the injured Samuel Eto'o up front for Chelsea this weekend, while Ashley Cole could return in a defence that will continue to be without David Luiz, who has returned to training but is not yet match-fit.
Southampton have made great strides in a short space of time under Mauricio Pochettino and begin the weekend in fifth place, just two points behind Chelsea and with a superior defensive record.
Pochettino has pitted his wits against Mourinho before but tasted only defeat when his Espanyol side played Real Madrid.
Espanyol didn't even score a goal in those fixtures but the Argentinian has a better record against Chelsea.
Last season Saints won 2-1 at St Mary's in March, when Rafa Benitez was still in charge of Chelsea, but will go into the game on the back of a 2-0 defeat at leaders Arsenal.
The clinching goal was the result of a debatable penalty award and defender Jose Fonte, the man penalised for shirt-pulling, called upon referees to be more consistent.
"I did have my hand on him but I just wish the referees would be consistent," he said.
"If they give that penalty why don't they give penalties like that every week against Arsenal and Man United?"