Napoli midfielder Marek Hamsik says they're wary going to Chelsea for their Champions League second-leg next week.

Napoli will be defending a 3-1 lead.

"We are trying to approach things one game at a time," began the Slovakian on Marte Sport Live.

"Now there is Cagliari, but everyone is waiting for Chelsea. Milan suffered a lot in London so we must leave no stone unturned.

"We must do what Milan did not do in their first half, where they suffered so much. We need maximum concentration.

"Yesterday Chelsea won in the FA Cup with [Roberto] Di Matteo on the bench. A new Coach always brings a shock and a change of attitude. This is to our disadvantage, but it must not change our approach.

"Chelsea will attack, so our counter-attacking must be deadly. [Edinson] Cavani and [Ezequiel] Lavezzi are phenomenal in that respect.

"We are thinking only of ourselves, though, and will follow Mazzarri's direction that has proven great for preparing for games under."