He insists it will take a miraculous performance for them to progress because of the injuries and fatigue affecting his players.
Damien Duff (hamstring) and Arjen Robben (ankle) are both consigned to the bench after failing to fully recover from injuries, while several other players are shattered following their efforts in winning the Championship at Bolton on Saturday.
But Mourinho said: "Motivation can make miracles. Chelsea are tired but ready to go to the final. Liverpool rested six or seven players this Saturday, but with a little more effort we can get to the final. We played our best team at Bolton because winning the title would help us forget our fatigue. We're confident that we can win.
"I said last week that details could make the difference. At Stamford Bridge the game was very balanced but we deserved to win 1-0. Now I think the game will be very balanced and only a detail will determine who goes to the final."
The absence of Duff and Robben from the start is a blow for Chelsea, but Mateja Kezman is convinced the Dutch winger, his former PSV Eindhoven team-mate, can still have a major impact on the game
He said: "I know how important it is for Arjen to play in this game and he will try everything to play against Liverpool. He's a fighter and wants to play, but sometimes injuries stop you. I know he is very strong mentally because I was with him at PSV and he showed a great attitude. He was injured several times and came back. He's a very tough boy."
