The Daily Mirror is reporting that the Red Devils have accepted that they are unlikely to be able to land Dier from Spurs after being told by the north London club that he is not for sale at any price.
The Red Devils are thought to be on the lookout for a holding midfielder this summer as Jose Mourinho prepares for his second campaign in charge at the club.
The same story claims that Manchester United have reached a similar dead end in their bid to sign Serbian midfielder Matic from Chelsea this summer, with the Blues thought to be reluctant to sell to a direct Premier League rival.
The likely failure to land either Matic or Dier could open the door for Manchester United to sign Fabinho from Monaco this summer.
The Sport Review exclusively revealed last week that the Red Devils are targeting the Brazilian as one of their top transfer targets this summer.
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