That’s the opinion of ex-Red Devils defender Gary Pallister, who sent the former Monaco winger a warning ahead of this campaign.
Since joining Manchester United for £36million, the Frenchman has adequately demonstrated his natural ability with a ball at his feet – notably in the Red Devils’ friendly win over Real Madrid on Monday.
However, there have been question marks over the youngster’s head, as he lacks consistency and has at times struggled to impress Mourinho.
Speaking exclusively to 888sport, Pallister acknowledged Martial has immense talent but warned he is running out of time to stake a permanent claim to the first team.
“It was a tough year for Martial. He had problems off the pitch and at times he looked disenchanted,” explained the former Red Devils man.
“Jose questioned his attitude a few times last season and what he was doing on the pitch but he’s had some good moments in the pre-season games and hopefully he learns from last year.
“Old Trafford is a goldfish bowl and he will be under pressure but there is no doubting the talent that he has.
“He has pace and power but last year I don’t think his head was in the right place. It is make or break time in a way and he has to ensure he starts the season well.”
Read the full 888sport interview with Gary Pallister, including his thoughts on which club made the best signing of the transfer window.