Pogba has regularly been under scrutiny since rejoining the Red Devils for £89 million in 2016.
Mkhitaryan believes his former teammate, who has five goals and six assists in all competitions this term, has been judged unfairly.
The pair will face each other on the pitch on Thursday when Roma visit Old Trafford for the first leg of their Europa League semi-final.
And Mkhitaryan has discussed how Pogba’s “personal life” often impacts the opinion critics have of the French midfielder.
“It doesn’t matter if you are Marcus Rashford, Paul Pogba or someone else, they will see something in you, small details to criticise,” the Armenian told The Athletic. “When Paul was playing everyone was criticising him for his hairstyle. I don’t think that has something to do with football, that’s his personal life.
“If he plays bad, criticise him for his bad performance, not his hairstyle. That’s not good. It has nothing to do with football. And you know, some people that don’t know him, some people who haven’t trained with him or played with him they don’t see these kinds of things.
“You have to be in the team, you have to see the way he trains, the way he thinks, the way he suffers and then say if he played good or he played bad.”
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