Martial has recently rejected the offer of a new five-year contract at Old Trafford due to his lack of game time since Alexis Sanchezs arrival from Arsenal in the January window.
But it has not just been the Chileans impact that has prompted Martial to fall down the pecking order, with Mourinho also concerned about his application in training and concentration levels.
And now the Daily Mail report that the drama surrounding Martial could prompt Mourinho to re-think his stance that United will not sign any more attacking players.
The Portuguese coach has previously insisted that it would be defenders he primarily targets this summer, but if Martial leaves – a bid of £60m is thought to be enough to tempt United to sell – they would need fresh attacking reinforcements.
Mourinho still retains an interest in Real Madrid star Gareth Bale, while he would also love to add his old Chelsea playmaker Willian to Uniteds ranks.
Bale, whose preferred position on the right would be perfect 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 Zidanes plans.
Willian, meanwhile, has had another strong campaign for Chelsea and the soon-to-be-dethroned Premier League champions would rather avoid strengthening a rival – especially after the impact Nemanja Matic has had.
There is another name United have discussed, and that is Watfords Brazilian winger Richarlison; his form has tailed off since Marco Silvas dismissal but he still commands a £40m price tag.
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