Martial fell out of favour under Jose Mourinho after the arrival of Chilean international Alexis Sanchez in the winter transfer window.
While he made 45 appearances for United last season, he started only 18 in all competitions, and was unable to get ahead of Romelu Lukaku, Jesse Lingard and Marcus Rashford in the pecking order.
Missing so much first-team action appeared to have cost the 22-year-old forward a place in the French World Cup squad, and he has been linked with a move away, with clubs such as Juventus, Arsenal and Chelsea linked with the player.
Anthony Martial in the Premier League for Man Utd:
• 2,632 minutes
• 11 goals
• 4 assists
• 1,558 minutes
• 4 goals
• 6 assists
• 1,584 minutes
• 9 goals
• 5 assists
— Squawka Football (@Squawka) June 13, 2018
In an interview with RMC Sport, his agent Philippe Lamboley confirmed his desire to leave, saying:
‘After thinking about all the possibilities and settings, Anthony wants to leave Manchester United.
‘There are many parameters, for now it’s premature to talk about it [the reasons for his decision]. Anthony will speak later to discuss all of this.’
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Lamboley went on to say that contract negotiations had stalled between the two parties, leading Martial to conclude he was not truly wanted:
‘United wants to extend Anthony’s [contract] and do not want him to leave but we do not find agreement for several months.
‘I think that when Manchester United, which is the most powerful club in the world, it must be remembered, does not find an agreement in eight months of negotiations, it is that it does not really want to make it an important player.’