"You learn from losses as well as wins," he told UEFA.com on Monday. "In Milan, we suffered a lot, but we managed to bounce back at home. Tomorrow will be another difficult match and we will have to be focused to avoid making the same errors as in Milan.
"Against them, we were reminded how important it is to score in the first leg. We hope to manage that tomorrow, even though we'll host the return leg again. It's important to be at 100% for 180 minutes."
The second leg of the tie will be held at Camp Nou in Barcelona next week.