Chelsea cannot keep relying on luck, warns Fernando Torres, after 3-2 victory over Shakhtar Donetsk We know we have to improve. We have been creating problems for them, pressing and creating chances from their mistakes, but not when we have the ball like we're used to. This kind of situation cannot happen again because, especially in the Champions League, at times like these you can be out. Torres, though, insists he would rather Chelsea were lucky than unlucky and hailed the never-say-die spirit which played just as big a part in last season's Champions League triumph. "When we needed to win, we did," he added. We did it against Valencia, Napoli and Barcelona - also the final against Bayern Munich. This was really the first big test of the season and we did it as well. We were a bit lucky - I think maybe the draw was the more fair result - but Chelsea has this special thing that no-one can buy. That's good. We have to keep the good luck on our side. Defender Gary Cahill admitted Chelsea had been under siege last night. "At times, there were four, five players up front," he said. They've got a lot of pace in the team as well, so I'm glad we don't play against them every week because they really impressed me. It makes the win even sweeter in the last minute of the game. It's a massive three points for us. He added: "We knew leading into the game how big three points would be. The manager stressed that to us. We keep pushing and pushing and pushing. We never know when we're beaten. Looking ahead to the penultimate Group E game in Turin, in which victory would seal Chelsea's qualification, Cahill said: "It's important we keep our foot on the pedal."