Los Blancos eased past their local rivals in the first leg of the semi-final, but the Atleti man believes that it is still all to play for in the return game at Vicente Calderon.
He told reporters: "You saw what happened on the pitch. We didn't have any luck and couldn't play the game we wanted.
"Madrid have the advantage. It'll be difficult but there's always hope. They weren't more intense but had more of the ball but if that first goal doesn't go in [off Emiliano Insua] then things are better for us.
"In football everything is possible. We will give everything for the team and the fans, because that's what they deserve."
Diego Simeone's side are top of La Liga.