Barcelona goalkeeper Marc-Andre ter Stegen believes some things to address internally despite winning 2-1 at Slavia Prague on Wednesday.

The German was at his best again for the Catalans, who just about escaped with the points.

"We haven't played at the level we wanted," he said afterwards.

"Luckily, we've taken all three points, which is obviously the most important thing.

"But I think we need to talk about some things."

When pushed on whether the issue was tactical or mental, the goalkeeper didn't want to let their secrets out.

"I think that's something we have to look at ourselves," he said.

"I won't say it here because it's more internal.

"It's not my thing. I'd like to speak to the players who were on the pitch first."