The Sun is reporting that the Portuguese head coach has grown impatient with the France international following his inconsistent performances in the Manchester United team.
The same article states that Mourinho has become infuriated with Martial’s persistent angling for a move away from the 20-time English champions this summer.
According to the same story, Manchester United will activate a clause in Martial’s contract that will extend his current deal until the end of the 2019-20 season.
As a result, Manchester United will be able to demand £50m for a player who Louis van Gaal signed in a £36m deal from Ligue 1 side AS Monaco in the 2015 summer transfer window.
The Sun goes on to emphasise that Mourinho will only sell Martial at the right price and the Manchester United boss is reluctant to allow the Frenchman to move to another Premier League side.
Martial has not shortage of suitors amid reported interest from Chelsea FC, Juventus and Borussia Dortmund in the summer transfer window.
Manchester United finished in second place in the Premier League table last term.
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