The west London club are in danger of being eliminated from the Champions League following a 3-1 defeat to Napoli in their last-16 first leg and they currently sit 17 points adrift of the Premier League summit. \"I think they will have to analyse what is going on and sort it out quickly,\" Zola told Sky Sports. Villas-Boas\' side are now without a win in five games and see their status in the FA Cup also under threat after a home draw with Birmingham forced a fifth-round replay. And Zola, who played almost 300 times for the Blues in a seven-year spell at Stamford Bridge, believes they may struggle for success this season. He continued: \"Psychologically at the moment they are a little too fragile and you cannot afford that, especially at this stage of the season. \"You have to know what you\'re doing and you have to do it 100% convincingly.\" The return leg against the Italian side is played on March 14 at Stamford Bridge.