Arsene Wenger has warned his Arsenal players to beware Napoli's strength on the counter-attack when the sides meet at Emirates Stadium on Tuesday.
Both sides began their Champions League campaigns with a victory in Group F and produced an entertaining 2-2 draw when they met at the Emirates Cup in August.
"We know from the Emirates Cup that they are a good side but we know as well that when you want to qualify then home games are vital"
Wenger says he learnt lessons from that meeting and is pinpointing Lorenzo Insigne as a key element of the Italian side's ability to quickly turn defence into attack.
"He [Insigne] is mobile, he is not tall but quick and very good in the transition from defence to attack," the manager told Arsenal Player. "He is a good dribbler as well and is an intelligent mover. That makes him an interesting prospect.
"That's what struck me as well in the Emirates Cup - when they win the ball they come out very quickly with Callejon, Hamsik, Insigne and Higuain, [who] come out like bombs all the time they win the ball. The transition from our side from offence to defence will have to be very quick."
Victory for Arsenal on Tuesday would represent a big step towards qualifying for the tournament's knockout stage. Napoli beat Dortmund in their opening game and Wenger is well aware of the quality last season's Serie A runners-up possess.
"They had a surprising result for many people because Dortmund reached the final last year in a very emphatic way," he said. "To beat them certainly is something special and that will lift their confidence. We know from the Emirates Cup that they are a good side but we know as well that when you want to qualify then home games are vital.
"We have started very well but you know if you win the second game at home you have a good chance to qualify. But I wouldn't say it's already a decisive game.
"It's a game that will have a great weight on the end result of the qualifying teams. Let's deal well with that situation then we will be in a very positive mood to finish the job."
Referee: Milorad Mazic (SRB)
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