Chelsea boss Mauricio Pochettino says a fully fit Ben Chilwell is making the difference.
Chilwell impressed for their Carabao Cup semifinal win against Middlesbrough.
Pochettino said: "It is really good because he is one of our captains. But of course, with him, we haven't had him for the whole season and now it is another period for him to cope for 90 minutes.
"We know what we are doing and today he added the experience and quality.
"I am happy to recover this kind of player because we are going to get the benefit."