The Blues have a slim lifeline after Juan Mata’s away goal just over two weeks ago, meaning just two goals, without reply from Walter Mazzarri's side, will see them through.
The midfielder pointed to previous performances against strong sides, especially their 3-0 triumph over Valencia in a must-win tie in Europe earlier in the season, and recent victories as the reason behind his confidence.
He told Chelsea's official matchday programme: "We had our opportunities to score in Naples and we didn't take them, but I think if we play well, we will have lots more chances to score at home - especially with the support of our fans.
"I think back to December, when we won the games against Newcastle, Valencia and Manchester City with some excellent performances.
"I don't think it's too difficult to score two goals - or maybe even more - at home, so that makes me confident we can go through to the next round."
Napoli boss Mazzarri has claimed he is not intimidated by Wednesday’s opponents, but spoke of his anger at his side conceding two late goals during their 6-3 Serie A victory over Calgari on Friday night.
He told reporters: "I got angry because, even if the result was safe, we shouldn't have conceded the last two goals.
"We cannot relax even for a second, because that way we concede. We've got to reflect on that.
"I am not worried about Chelsea, but the fact is we cannot afford similar defensive errors against Chelsea."