Manchester United boss Jose Mourinho, speaking after their 4-1 friendly defeat by Borussia Dortmund admitted that the opposition showed what a difference one month's preparation can make.

"My thoughts are simple.

"I know in pre-season the team in the advance stage of preparation looks better. It happens year after year. It was too obvious. We knew after 10 minutes that one team started training a month ago and played four games.

"In the second half it was better. I think 3-2 was more natural than 4-1. They showed good quality and at an advanced stage."

He added: "I don't think I can analyse them with such difference in preparation. It was like F1 against F3. They are much sharper, so difficult to judge. But it is quite easy to get three, four, five - the quality and mentality and personality is there.

"(It's been) 10 days of work. People really tired. High quality opposition. Unfair to make any decision. Day by day they are starting to win my trust.

"The reality is even in this situation we have six players still in Europe, plus (Wayne) Rooney and (Chris) Smalling who are only training.

"That is eight not involved. Obviously some are not going to stay in the squad and it will be different than it is at the moment."