Ferguson admits the way they played in the first leg gives him real cause for optimism.
He said: "We could have scored five or six.
"Unusually for Robin van Persie, he missed two great opportunities and their goalkeeper made a couple of good saves.
"Danny Welbeck missed one just before half-time.
"We expected Madrid to have a lot of possession, there was nothing that worried me and they weren't carving us open."