Manchester United interim head coach Ralf Rangnick has said that the Red Devils need 'open-heart surgery' to address their problems.

The 20-time English champions will again finish the season trophyless and face an uphill task to qualify for the Champions League, having lost two of their last three Premier League matches.

Rangnick will step aside for the arrival of Erik ten Hag this summer, and it is still unclear whether the German will be remaining at the club on a consultancy basis despite the widespread reports.

The 63-year-old has been outspoken regarding the club's issues since his arrival towards the end of last year, and he has admitted that 'open-heart surgery' is required at Old Trafford.

"You don't even need glasses to see and analyse where the problems are. Now it's only about how do we solve them?" Rangnick told reporters.

"For me it's not enough to do some minor amendments, some little issues here and there and little cosmetic things. In medicine, you would say that this is an operation of the open heart. There are more things to be changed than some little things here and some minor things there but this is the good thing.

"For me, 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 still believe it doesn't take two or three years to change those things. This can happen within one year.

"Other clubs not too far away from here have shown that it doesn't take two, three or four years, it's possible within one, two or maybe three transfer windows."

Rangnick has also said that there will be 'significant changes' in the Man United squad during this summer's transfer window.