The club faces transfer debt repayments of about €222 million this year.
Manchester United are reportedly aiming to clear €1.4 million a week from their wage bill this summer to fund future signings.
Departures including Casemiro, Jadon Sancho, Marcus Rashford, Rasmus Hojlund and Andre Onana could free up more than 72 million annually.
Finding a replacement especially for Casemiro, is understood to be a key priority.
The club also faces transfer debt repayments of about €222 million this year.

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