Former Manchester United manager Jose Mourinho once told Real Madrid midfielder Casemiro that he would become the "best central midfielder in the world" amid the Reds' interest in his signature.
As reported by the Manchester Evening News , United have contacted Madrid about the possibility of signing the Brazilian midfielder before the transfer window closes in just over a fortnight's time.
The Reds' move for Juventus midfielder Adrien Rabiot has broken down and they are desperate to add to their midfield options.
Barcelona midfielder Frenkie de Jong remains an active target for United, although it is now more than three months since they first registered their interest.
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