Caption London - Arabstoday   Chelsea goalkeeper Petr Cech has admitted that his side's 3-1 UEFA Champions League defeat to Napoli was a sign that the English Premier League side's crisis is far from over. Injury-plagued Chelsea are already struggling in the league and the FA Cup, leading to media speculation that club owner Roman Abramovich is looking to replace manager Andre Villas-Boas. After Tuesday's defeat in Naples, the London giants now face a tough call to save their last 16 tie in the 14 March second leg at Stamford Bridge. However. while Cech believes the Blues can overcome that setback, the Czech international lamented the "silly mistakes" that have given Chelsea a mountain to climb in three weeks time. "We can see the crisis is still ongoing. Unfortunately, our poor run continues and the result from Naples obviously didn't help our situation," Cech said on his website. "It ended up exactly the way we didn't want it to. But everyone who was on the pitch is to blame. We make silly mistakes and we pay for it." Cech believes that a 2-0 victory "is still manageable, that's no miracle in football". But he added: "We mustn't concede, that would make things very difficult. We're definitely not giving up. We're still not out, and we have to fight to advance." Chelsea's defence was hit by the absence of captain John Terry, who was ruled out of the Napoli game with a knee injury and is set to be sidelined for six weeks. "He had been out for some games so we had to get used to playing without him. But it's definitely a loss," said Cech. He also bemoaned the loss of Portuguese defender Jose Bosingwa, who limped off the after 12 minutes. "But that's life, we'll have to cope with it somehow," he said.