Anthony Martial is reportedly one of four Manchester United players who Ed Woodward is unwilling to sell.
The French forward went AWOL during United's pre-season tour following the birth of his son, Swan, in Paris and looked certain to complete a move away from Old Trafford.
However, reports suggest that Martial has performed a U-turn and is in talks over a new five-year contract with the Red Devils in the hope that Mourinho will be sacked.
Executive vice-chairman Woodward, who angered Mourinho by refusing to sanction bids for Toby Alderweireld and Harry Maguire during the summer transfer window, blocked Martial's attempts to leave.
The Telegraph suggests Woodward now has total control over the club's transfer dealings after a summer of infighting with Mourinho.
It's claimed the Portuguese has been told that Martial, Marcus Rashford, Jesse Lingard and Luke Shaw will not be sold at any cost.
The quartet are viewed as central to United's long-term future and Woodward has made this clear to Mourinho.
Club legend Ryan Giggs urged Martial to knuckle down and fight for his place in Mourinho's starting XI at United.
'I hope Anthony Martial comes back and fights for his team and then hopefully he will be able to concentrate on his football.
'We have seen glances of his qualities, which are definitely there.
'But it's up to him to prove he deserves a starting place again.'