The Spaniards suffered a 1-0 defeat in the first leg in Lyon on Tuesday night.
“In football anything is possible. We’ve lost here but we have a game at home in which we can repeat what they did here,” said the Portugal international.
“I’m calm. In this competition you have to suffer. I’m sure that we will give a good answer in the return game and that we will win.
“The Bernabeu will help us. We will have to give to give it everything from the first minute until the last. The tie is not lost.”