Louis van Gaal has warned Manchester United and its fans not to expect miracles right from the start of his reign at the club.

The Red Devils endured a difficult time last season under then new manager David Moyes, but it did not improve throughout the season, as United went on to finish seventh in the league failing to qualify for any European competitions.

The Dutchman believes that it will take some time for his methods to take effect, and that the players also will need time to adjust to his ways. He is insistent that it is not the players' legs but the brains that need to be coached into thinking and playing in a certain way.

"Every club where I have been, I've struggled for the first three months," van Gaal said, as quoted by Goal.

"After that, [the players] know what I want – how I am as a human being and also a manager because I am very direct. I say things as they are so you have to adapt to that way of coaching. It's not so easy.

"The way I train and coach is in the brains, not the legs, but the most important thing is they have to know why we do things. When they do, the footballer is not playing intuitively," the former Netherlands coach explained.

"A lot of players are playing intuitively and I want them to think and know why they do something. That process is difficult at first and in the first three months. It takes time," he said.

However, van Gaal has assured that once the settling in period is over, the Red Devils will do well. The coach was looking at his stint at Bayern Munich to give an example of how the Bundesliga side struggled initially, but eventually found success under his management.

"When we survive the first three months, it will be the same as for me as it was at Bayern Munich. At Bayern, after the first three months, we were sixth or seventh and we were third in our Champions League group," van Gaal continued.

"We had to win at Juventus and did – that was the turning point. Now United have me, a new manager, so new chances for the players but we have to create a way of playing that isn't the same as before and that's difficult for them.

"They have to perform under pressure and have to decide [what to do with the ball] within one second and that is not easy," the Manchester United manager concluded.