Manchester United midfielder Fred says they cannot afford any lapses in their pursuit of Europa League glory.
United face Copenhagen in Cologne on Monday for a place in the semi-finals, where they could meet Premier League rivals Wolves for a place in the final.
"There are two important games and a single match in the final," said Fred. “You have to make sure you're highly prepared, you can't make mistakes.
“In league football you still have the chance to recover – if you make a mistake and lose the game you can still recover later in the competition.
“In tournaments, if you lose a game by a certain margin of goals, it's difficult to come back.
“So you need to concentrate even more. I think that's what's most important for us. That will be the biggest test.
“I like playing all types of football, whether it's a tournament or a points-based championship like the Premier League, but I think in tournaments you need to concentrate more."
