Napoli coach Walter Mazzarri feels they can still improve their football in Europe.
Mazzarri was pleased with victory over Villarreal in the Champions League.
He said, "We still have little experience in Europe, so we expend lots of energy: we must grow in this.
"Are we offensive? Thank goodness you do not talking about Napoli relying too much on comebacks. Even last year we often crushed opponents by 70 minutes.
"Tonight at one point we dropped too much and I'm angry: if we did not have the goals, we would have suffered.
"After the Europa League last year, I was sure that my Napoli would have had the right approach. I am proud that this team will follow me all the way."