The Times is reporting that the French striker has become “disillusioned” at his failure to hold down a regular spot in the first team at Old Trafford this season.
The same story says that the Red Devils have recently offered Martial a new five-year contract but he has not yet agreed to sign it.
The 22-year-old striker’s current contract at Old Trafford is due to expire at the end of next season, although the Red Devils do have the option to extend by a further year.
Martial has found his playing time to be somewhat restricted this season and he has only made four starts for Mourinho’s men since Alexis Sanchez’s arrival at Old Trafford from Arsenal in January.
The France international has scored nine goals and made five assists in 26 Premier League games for the Red Devils so far this term, but he has only started 16 of those matches.
Meanwhile, Martial will be hoping to feature for Manchester United when the Red Devils return to Premier League action on Sunday with a home clash against West Brom.
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