The on-loan Chelsea keeper faces a huge test at the Nou Camp.
The Belgian told AS: "We have a good team and can beat them. It is not impossible to win at the Nou Camp.
"Barcelona are a very, very strong team with great players but we have a good side. It is a very important game but we have no fear."
Barca's last home game, against Osasuna, ended 8-0 to the Catalans.
"They have great footballers and for me and the defence it will be the ultimate test against one of the strongest teams in the world," he added.
"But we are confident we can beat the Blaugrana."