The 22-year-old Martial joined United from French side Monaco in the summer of 2015 and has impressed since then.
Mourinho has always made it clear that if a player is unhappy and wants to move he wold not stand in his way.
Martial's return of 24 goals in 82 appearances is good but not spectacular while his struggles to get regular game time have not helped.
The reports have even suggested that Martial has rejected a new contract offer from Man United, with his current deal due to expire at the end of next season (with the option of an extra 12 months likely to be activated in the near future regardless of the impasse).
His lack of playing time is the main reason for the refusal according to RMC Sports.
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Otherwise, if we accept this result and say we were unlucky, we are not building anything positive for the future'. But with Chelsea failing to win, they are ten points off Liverpool and fourth placed Tottenham Hotspur.
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It further reads, "We will not screen the film in it's entirely until the Los Angeles premiere shortly before the film's global release".
Martial has registered 11 goals and ten assists this season, but has seen ex-Arsenal ace Sanchez eat into his minutes, with the France ace not scoring since January.
According the same article, Juventus have been warned that Martial will cost around £60m and the Serie A giants will have to see off competition from Atletico and PSG.
If he does opt to sell Martial, Delaney added United would want a figure in the region of £60 million for him.
The youngster is a big fan favourite at Old Trafford and fans would not be pleased if Mourinho let him go.
Bale, whose preferred position on the right would be ideal for United, has fallen out of favour at Real and is believed to be considering his future at the club, with the likes of Lucas Vasquez and Marco Asensio now ahead of him in Zinedine Zidane's plans.