Napoli star Morgan De Sanctis has told Sky Sports that they arrive in London confident of knocking Chelsea out of the UEFA Champions League.
The Naples giants hold a 3-1 advantage from the first leg in Italy, as they look to clinch a place in the quarter-finals.
Since the match at Napoli, Chelsea have changed their coach with Andre Villas-Boas sacked and replaced by his assistant Roberto Di Matteo.
De Sanctis admits the change of coach will make it harder to predict what system will be used by Chelsea, but they remain confident of progressing.
"Our rival has changed their coach and this does generate doubts about the systems and the game," he told Sky Sports.
"But the normal thing is that Chelsea will search for the goal from the first minute, which will leave us chances to attack.
"We have improved our level in the last few weeks, so we arrive in perfect condition for this battle in London."
De Sanctis admits that the whole complexion of the tie has changed since the draw was made late last year.
He said: "Things have changed so much from the day of the draw, Chelsea were the favourites at the time but our showing in the San Paolo has seen things move to us.
"Now people have doubts [about Chelsea] and Napoli now has the chance to progress.
"And this is not by luck, we were superior in the first match."
Despite the confidence in the Napoli camp, the Italian international keeper admits things will not be easy at Stamford Bridge.
"I am not expecting an easy match, but neither constant pressure in our area," he said.
"We know what to expect and have prepared in detail for it.
"Chelsea has the experience, but we have a two-goal advantage and this gives us a big chance.
"We merited the goals but at Stamford Bridge, we have to avoid pressure and play our own tactics and look for our own efficiency in attack.
"In the last few days we have worked very hard on our defensive lines, they will look to mount serial attacks but we must stop this.
"And to be honest I do no fear the Blues forwards, our attack is sincerely more dangerous."
He also paid tribute to their South American forwards Edinson Cavani and Ezequiel Lavezzi , who both scored in the first leg.
"Lavezzi and Cavani is one of the best attacking pairs in European football," he said.