The Portuguese coach was appointed as the Red Devils’ new manager back in the summer of 2016 just days after Louis van Gaal led Manchester United to the FA Cup title.
Mourinho was available after having been sacked by Chelsea FC in December 2015 following the disastrous start to their title defence.
Mourinho led Manchester United to a sixth placed finish in his first season at Old Trafford but guided them back into the Champions League thanks to their Europa League triumph.
Van Gaal insists that he has nothing against Mourinho for taking the job but says that he felt mistreated by the Manchester United board.
Van Gaal said in an interview with German newspaper Sport Bild: “I am not disappointed with Jose Mourinho. Every coach wants to train Manchester United, it’s one of the biggest clubs in the world.
“I think Jose wanted that, too, and although he was able to do so in 13th place, he had a chance on a fantastic team like Chelsea. I was in fourth place! I still do not blame him.
“What I find wrong is when a CEO says we’re totally happy with you, do not believe the press. Then you win the FA Cup and still be fired.”
Meanwhile, Manchester United will return to Premier League action on Saturday when they host Stoke City at Old Trafford.
The Red Devils are currently in second place in the Premier League table as they bid to finish as closely to Manchester City as possible.
Manchester United will also take on Tottenham Hotspur in the FA Cup semi-finals next month as they bid to end the campaign with a trophy.
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