Enzo Maresca has made it clear he wants Chelsea to sign a new centre-back after losing Levi Colwill to injury. Colwill has become a key player for the Blues but suffered a serious knee injury in training and is expected to miss the majority of the season. Though Chelsea have a raft of centre-back options, Maresca has made it clear he believes better quality is needed. It comes just weeks after they spent an initial £37million on the Ajax centre-back Jorrel Hato. “He is okay,” Maresca said of Colwill. “He is aware that he has to be out for a long time. It is a big loss for us. You know how important Levi has been for us last season, for the way we want to play. “We said many times that we are able to create chances and to attack in the right way if we are able to build in the right way. Levi was a huge part of our build-up and now he is out and we are going to try to find a different solution.” Maresca was then asked whether that “different solution” meant finding the right player internally or making a new signing. “We are trying to find a solution internally, but the club know exactly what I think,” Maresca asserted. “I think we need a central defender. We are looking for an internal solution but, as I said, the club know exactly what I think. “We have a fantastic squad. We are happy with the squad we are, no doubt. But we said many times that when the window is open, anything can happen.” Chelsea had an unusually short pre-season because of their run to Club World Cup glory in the United States. On Sunday, they face Crystal Palace at Stamford Bridge in their Premier League opener. “We guess we are ready,” Maresca said. “It has been quite a short break, but we will try to be ready. “For sure, it’s something new. Unfortunately we don’t have the answer, because it’s something new.”