Villas Boas - Chelsea owners backing me in private - CNN.com February 20, 2012 -- Updated 2143 GMT (0543 HKT) Andre Villas Boas has cut a lonely figure on the Chelsea touchline this season as his side have struggled for form. Under-fire Chelsea manager Andre Villas-Boas confirms the club's owners still support him He says speculation about his future would be quelled if owners backed him publicly Chelsea face a tricky Champions League last 16 clash against Italian side Napoli (CNN) -- Under-fire Chelsea manager Andre Villas-Boas has again confirmed he has the full backing of the club's owners -- although he admitted his tenure would be easier if they publicly supported him rather than doing it in private. The 34-year-old Portuguese faces a make-or-break Champions League last 16 clash against Serie A side Napoli, but has again had to field media questions about his future ahead of Wednesday's first leg in Italy. Speaking to reporters, Villa-Boas said: "You have to understand that this club, from 2004 up to now, has made dramatic changes. It's the richest part of Chelsea's history, full of trophies and success, and you want to perpetuate that into the future. To do that, you have to sometimes make changes because you cannot sustain the same habits that you had in 2004, when this environment and team was created to make a winning side. He continued: "These words would be more valuable coming from the top. I cannot keep saying them but, as the voice of the club, I will continue to perpetuate this message because this is what we believe in. In terms of the results this year, the speculation is normal given the cultural past of this football club Andre Villas-Boas With Chelsea on course for their worse season under the reign of owner Roman Abramovich -- the club currently lie fifth in the English Premier League -- Villas-Boas conceded that he understood the speculation regarding his future due to the Russian's previous habit of sacking managers quickly. In terms of the results this year, the speculation is normal given the cultural past of this football club, but you have to understand that there's a different perspective now. That doesn't take any responsibility for what's happening now, but we have a three-year project to change not only the team, but the culture and structure of the club. There's a lot we needed to do, a lot of plans, so that's why I'm excited about the future. Having said that, we have to build a team to win trophies from the start. Chelsea have gone four matches without a victory in all competitions -- and have only won four of their last 13 games -- but Villas-Boas is confident his under-performing side can get a positive result in Naples to give them a chance in the return leg. Whatever happens here tomorrow will not be decisive for the running of the tie. Stamford Bridge, as you know, is a great stadium for European nights, which is why we wanted to finish first in the group to get the second leg at home and get a positive result. He added: "But we have to be conscious of Napoli's strengths at the San Paolo, a team that has been built up with Europa League qualification last year and now have done very well in the Champions League. Tomorrow is all about awareness of Napoli's strengths and, hopefully, to bring a positive result back to Stamford Bridge.