Jose Mourinho's side fell to a 1-0 defeat against the Toffees on Saturday after spurning a succession of chances at Goodison Park and the Belgian believes that they need an immediate response at Stamford Bridge.
"We need to win because Chelsea is a big club and, if we lose two games, it's very bad for us," he told reporters ahead of Wednesday's clash.
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The Belgian's comments were echoed by Juan Mata, who insists that he is now fully fit after starting under Mourinho for the first time in that defeat.
The Spaniard added: "After one defeat you just want the next match to come as soon as possible and probably the Champions League is the best way.
"These nights at Stamford Bridge have a different feeling, even more so since we won the title two years ago. This competition brings great memories to all of us and makes us feel really excited.
"I'm looking forward to play at home again and I hope we win so we can face the next Premier League game with a good taste in our mouths.
"The next few weeks ahead are very intense - five games in just 14 days. In order to get ready for them is very important to get confidence and to be positive."