Chelsea stuttered to a disappointing 1-1 home draw with Birmingham City in the FA Cup fifth round on Saturday, after their Italian opponents eased to a comfortable 3-0 win over Fiorentina on Friday.
And the Blues boss admits his side face a difficult task in beating Napoli over two legs, starting with an away trip to Stadio San Paolo on Tuesday night.
“If you go past Napoli then you can have a really good chance, depending on who you get in the draw – if you get a good draw,” Villas-Boas said.
“It will be a massive challenge. Everyone saw what Napoli did in a group which put another English team out.
“The Champions League is a competition that everyone wants to win. The players will feel much more tension and feel it much more.
“There are two weeks between the games and it’s important for us to be competent and to bring the game to Stamford Bridge with a win or a draw, ideally a scoring draw. Then we can finish the business here.”
Fernando Torres’ struggles in front of goal continued against Birmingham – and Villas-Boas replaced the Spanish striker at half-time, bringing on crowd favourite Didier Drogba in his place.
But Villas-Boas has once again issued his backing for the misfiring forward, insisting everyone at Stamford Bridge has faith in the 27-year-old.
“Everybody is desperate for Torres to score,” the Blues manager added. “Everybody pushes him, praises him in training and it will come with him getting opportunities.
“His confidence is low but we will have to continue to persist with our belief in his talent.”
• Napoli have drawn 10 Serie A games already this term, including seven in their last 14 league outings. They drew seven times all last season en route to a third-place finish.
• Eleven of the 31 league goals Chelsea have conceded this season have come in the last 15 minutes.
• Didier Drogba scored his 150th Chelsea goal against Aston Villa on 31 December, taking him joint fourth on the club’s all-time list.
• Napoli are six games unbeaten at home, winning four, since a 3-1 defeat by AS Roma on 18 December.
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