Manchester United boss Ralf Rangnick says Manchester United need a "major operation" to fulfil the club's potential.
Interim boss Rangnick is overseeing yet another trophy-less season at Old Trafford, with United now an outside chance for a top-four spot too.
Performances have been heavily criticised this season, while the club's recruitment policy has also come under fire.
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And Rangnick admitted that there are multiple problems and that the club needs "heart surgery" to recover.
"One of the very few good things is that it is crystal clear, it is not that difficult, you don't even need glasses to see what the problems are," he said.
"So now, it's only about how do we solve them, and for me it's clear, it's not enough to do some minor amendments, little issues, here and there, some minor cosmetic things. No, in medicine you would say this is an operation of the open heart.
"If this happens and everyone has realised that this has to happen and if people want to work together then it makes sense and I believe it doesn’t take two or three years to change those things. This can happen within one year."
United lost 4-0 last weekend to fierce rivals Liverpool and looked uninspired through a match that demanded passion, effort and fire.

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Captain Harry Maguire has drawn criticism for a series of poor performances, while the lack of strong leadership at the club has also been commented on.
And Rangnick accepted that United need strong leadership beyond the manager's office.
“For sure [strong leadership is needed]," he added.
"This is something that not just one single person as a manager can do. With all respect to Jurgen [Klopp] and Pep [Guardiola], I’m sure that they didn’t do all the things themselves [at Liverpool and Manchester City].
"There were also other people involved in those two clubs, people in certain positions, no matter what area it was, in order to rebuild and build something we want to build here. In all areas you have to have top people and they have to work together in a very close, reliable way.”
Ajax boss Erik Ten Hag will take over from Rangnick in the summer on a permanent basis.
The Dutchman has worked wonders at Ajax and was the preferred choice over Mauricio Pochettino, who has frequently been linked with the Old Trafford job.
And while Rangnick was full of praise for Ten Hag, he said that he will need more from his players and staff to succeed.
“All I heard from people who work with him is that he is a very good character, communicative, and does things himself,” Rangnick said.
“Obviously, he needs the assistance of all the people inside the club and he will get that and have the chance to mould a new team together with the scouting department and the board, which is necessary.
"The most vital part is that the club manages to get in the best possible players, and we have the attitude, the energy. We need positive energy for the new team and this is also important for the new manager."
Rangnick signed off on positive note, too, saying that the club had the infrastructure in place to succeed.
The German is expected to move to a directorial role and insisted that he wanted to remain a part of the club's development despite a tumultuous time in Manchester so far.
“I still see where we could develop. We have perfect training conditions, a great stadium, massive fan support, probably the best I’ve ever experienced apart from Schalke. Of course, I would want to be part of the process that has to happen.”
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