Martial struggled at Manchester United during the days of Mourinho, with the France international failing to replicate the same form previously showed by Louis van Gaal.
The 22-year-old will now strut his stuff under the guidance of Ole Gunnar Solskjaer, who was named interim boss earlier this week.
Martial was accused of lacking focus by Jose Mourinho during their time at Manchester United, leading to problems between the two Old Trafford heavyweights. And the player has now admitted that, when at school, he lacked focus.
Something that might even justify Mourinho’s own thoughts. “Being honest, I wasn’t all that!” he said when asked about his teenage years. “But for the town where I grew up, you couldn’t really be serious.
“It was just impossible, what with all my mates, and the environment we were in, you just couldn’t be that conscientious.
“But in spite of all that, I still tried to do the best I could because my mum and dad would be on my case – and they didn’t mess about!
“However, I did try to make the most of my studies, but it wasn’t easy.”
The United star also revealed how his family helped shape his footballing career.
Martial added: “I think it was me, really, then my family.
“I think they spotted from an early age that I had some talent but, after that, it was just playing for fun at the beginning.
“They never thought or said to me you absolutely have to become a professional footballer.
“It was more about having fun, and then I’d just see how things went for myself.
“So it was more playing for my own pleasure and, as time went by, I began to see that I could be, or at least try to become, a professional footballer.”
Martial could feature when United face Cardiff on Saturday night (5.30pm).