Real defender Fabio Cannavaro said at the final whistle: "It was a very strange game because Madrid has played very well and deserved a more positive result.
"We didn't get a deserved penalty, hit the post, controlled the game very well and Iker (Casillas) has not made any saves ... surely in Madrid it will be better.
"The Bernabeu is going to be far from easy for them."
Real midfielder Fernando Gago also said: "We gave a good performance. We enjoyed many chances, but could not finish them off.
"Personally, this has been one of the most complete games I've played since I came here. I feel better every game. I leave happy with my performance, but upset by the result."
Gabriel Heinze added: "We did not deserve to lose. In the second-leg, we will be favourites. We have the fans who will make the difference."