Mourinho said: "Now we must concentrate on Barcelona. I left my assistant in Milan so he could best prepare the training regime with the players. Now it's down to me and I hope the squad will be relaxed.
"On the bus ride home we're already working on Barcelona. I was there for three years and in that stadium your head is more important than your tactics.
"Stepping into that arena and saying you want to entertain is a difficult test in a player's career. It's going to be a real challenge of our character."
There are concerns over whether former Inter man Zlatan Ibrahimovic will be able to play.
"I am 99.999 per cent sure he will be on the field," smiled the Special One.