"When the players go to their national teams, I think a lot of them lose their concentration," he said. "We have seen this before with the breaks. When they come back, we lose a game and I think it's a dangerous time for us.
"It shouldn't be like this. If you want to win trophies and play for a big club, you have to play important games all the time. Whether it's for the national team or Champions League, you have to reach a level and stay at it.
"We have accepted it was bad last weekend and now we must try to be positive about the future. There are eleven games left, five of which are at home against teams around us and fighting for fourth and fifth."