However, he said that although not scoring and conceding two goals in the away leg makes qualification tough, Lazio are still "strong" enough to get through.
"It's not a good result for us," UEFA.com quotes Cana as saying. "You concede two goals and couldn't score any away goals.
"It's going to be tough to recover from this defeat but I believe we still have a good chance to go through. We have a strong side and we are capable of doing it.
"Tonight, we played a very serious game and showed our quality. With 11 players it would not have been the same result, but that's football – we just need to keep our heads high and look forward."