Chelsea boss Frank Lampard has tagged their Champions League fixture against Valencia a “must not lose” game rather than a “must win”.
Lampard’s side are second in Group H and will qualify if they win.
Chelsea lost 1-0 at home to Valencia in their opening game but Lampard says the defeat has “put us in this position and brought a sort of knockout football”.
“We were the better team but the lesson was, if you sleep for one moment then you get punished,” said Lampard.
“It’s a big test but we do not mind that.”
The Blues will be without the injured Callum Hudson-Odoi, while Ross Barkley and Antonio Rudiger have not travelled despite returning to training.
Lampard says Rudiger, who has been out since he was taken off in the 5-2 Premier League victory at Wolves on 14 September, is still working towards fitness after undergoing surgery on an issue with his pelvis.
Meanwhile, Valencia coach Albert Celades says the visitors are a “super” side and “one of the best in Europe”.
Chelsea have won nine of their last 13 games in all competitions, although they were beaten by Manchester City in their last Premier League outing.
Both sides are level on seven points, along with last season’s semi-finalists Ajax.
“It’s a great opportunity for us to try to reach the next round. But even if we don’t win we’ll still have a good chance,” said Celades, whose side travel to Ajax in their final group game.
“But we will go out to win the game first of all and then see what happens next. We are a big club and we have to have that type of mentality.”