The first leg ended in a 1-0 victory to the Gunners at Emirates Stadium on Tuesday, following a penalty goal by Robin van Persie.
“I’m convinced in the second match it will be different,” he told Sky Italia.
“In the first half we weren’t very good, but in the second one we have been much better, and this gives me hope for the second leg game.
“At the beginning we haven’t been able to keep the ball, a thing Arsenal did in a good way.
“The second half showed us what we will have to do at Stadio Olimpico in the next match.
“When (David) Pizarro came on things changed and he proved to be an important pawn for us. We must try to play with the ball on the ground.”