Boss Louis van Gaal says expectations at Manchester United are too great.
United have spent more than £320m on players since former manager Sir Alex Ferguson retired three years ago.
They will hope to win their first major trophy since Ferguson’s departure when they face Crystal Palace in the FA Cup final on 21 May, but Champions League qualification is out of their hands.
“We have to meet the expectations of the biggest club in the world,” said Van Gaal. “Expectations are too high.”
Dutchman Van Gaal replaced David Moyes as manager in 2014, and United finished fourth in the Premier League in his first season.
But the Red Devils are four points adrift of fourth-placed Manchester City this campaign, albeit with a game in hand.
Van Gaal said: “We are in a period of transition. It is not so easy.”
The 64-year-old was speaking before he presented David de Gea with United’s player of the year award, which the Spain goalkeeper won for the third successive year.
Van Gaal said his authority in the dressing room had been undermined by the intense media scrutiny over his position.
But the former Ajax, Barcelona and Bayern Munich boss remains confident in his ability.
He said: “When the media is writing for six months I am sacked already… I can cope with that. It is not new for me. For my players, it is not so easy.
“They are reading every day. What do you think about my authority? What do you think about the way they want to follow my advice, when their coach is showed like a nobody because I cannot do anything? But I am not like that. I am very arrogant. I am one of the best managers of the world.”
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