Pogba posted a message on Instagram after the game that notably did not include a reference to his club boss.
Paul Pogba said he needs to be happy to perform at his best for Manchester United, adding that he would be fined if he spoke his true feelings.
"I don't think there's any question that a player would say that under Fergie because you'd have been finished".
Pogba was pushed on his response and said that "if you're not happy, you can not give your best" when asked about what represents happiness and comfort for him.
But there is something brewing behind the scenes and there has been for some time after Mourinho left Pogba out of the team on multiple occasions last season and publicly criticized him. I have always been talking to my team-mates.
Pogba answered the call to take his place in United's midfield just 26 days after lifting the World Cup with France, a response which earned his manager's praise as well as the captain's armband.
"I am someone who is not (in) a role that I give to myself". "It's a different team, obviously".
"Having the armband, it's not like "oh, I will show that I am a real captain and have to do extra work".
Mourinho, who has cut a frustrated and grumpy figure during a transfer window in which United failed to sign any of his centre-back targets, hailed Pereira's "phenomenal" performance after United won their first game of the season.
Luke Shaw grabbed his first goal in senior football to double the lead with seven minutes to play.
But if Barca offer them the chance to make a profit on the player they signed for a then world-record fee of $115 million two summers ago, and someone who has never really hit top form consistently, should United snap their hands off?