If Anyone doubted that Chelsea are a team with a split personality, the fact was comically underlined by the post-match analysis of last Tuesday's 1-0 defeat in Marseille.

"Our performance was good," argued the manager Gianluca Vialli. "Apart from the result I'm quite pleased."

"It was a very, very poor display," countered the coach Graham Rix. "Our passing was poor and so was our crossing."

Of course, Vialli was merely doling out the banal propaganda that has marked his interviews of late, whereas the Yorkshire-man in Rix preferred straight talking.

But the fact remains that Chelsea performances are infuriatingly good and bad. Earlier this season they sailed through their opening Champions League games while their domestic form fell apart. Now they have ghosted up to third in the Premiership while their European form is starting to fray at the edges.

Another problem for Vialli is the form of his Stg £3 million midfielder Didier Deschamps, who was substituted after 62 muted minutes last week and was not even on the bench for Saturday's win at Newcastle.

In typically diplomatic fashion, Vialli played down suggestions that the 33-year-old was in the doghouse. "Someone who gives everything each time he plays needs a rest every now and then," he said.

"I understand that people don't know him as well as I do. Maybe they expect more skill and more elegance from a midfielder who captains France. But I look at how effective he can be, not how elegant he is or how many good passes he makes.

"He's very experienced and he's not here just to waste time or earn money in an easy way. He's here to win things because that's what he's used to and he always tries his best.

"It's quite important for a player to go back to the place where he started and play a great match but unfortunately that doesn't always happen.

"So he was disappointed last week but mainly with the result. Secondly comes your own performance and the main thing is how the team performed."

However, the impression remains that Vialli was making a point to Deschamps on Saturday and that tonight the Frenchman will be recalled to see if it has sunk in.

Marcel Desailly is expected to recover from a knee injury in time to play, but Roberto di Matteo and Jon Harley both face fitness tests.

Realistically, Chelsea probably have to win the game as they lie two points behind group leaders Feyenoord, level on points with Lazio and just one point ahead of Marseille.