The French midfielder, who returned to United in a then-world-record £89 million transfer in 2016, had a notoriously difficult spell under Mourinho, which culminated in the manager's dismissal in December 2018.
Pogba ultimately saw out his contract, leaving Old Trafford for a second time on a free transfer to rejoin Juventus in 2022.
His return to Italy was plagued by injuries and a doping suspension, which was later reduced from four years to 18 months. The 2018 World Cup winner has since signed a two-year deal with AS Monaco.
Pogba speaks on failed relationships with Mourinho
Speaking on the Rio Ferdinand Presents podcast, Pogba, who recently signed for Monaco after an 18-month doping ban, explained that the issues began to surface around his persistent injury problems.
"I don't have any problem with any coaches," Pogba stated. "I always respect [them]. They are the boss. That's the truth. They decide if you play or not."
He described their initial relationship as positive, noting Mourinho's personality. "We were very cool at the start, sending messages and stuff like that. He's a really funny man... really special, to be honest. And after a time, I think the injuries created that [breakdown]."
Pogba believes the relentless media focus on him contributed to the tension. "When always the media ask him questions about me, maybe it makes him a bit like, 'OK, is he done?'
“And this is the problem also with me; like a lot of people, they love to ask about me. Always Paul, Paul, Paul, and that probably pissed him off."