Pogba was named among the substitutes for United’s comfortable 2-0 win over Huddersfield Town on Saturday, only appearing as a second-half substitute.
The midfielder’s demotion was the most surprising of four changes, with Phil Jones, Anthony Martial and Ashley Young also losing their starting place from Wednesday’s defeat.
Scott McTominay, a United academy graduate, took Pogba’s place in Mourinho’s side, making only his sixth start of the season so far.
“I changed a few players and the intention was not to punish anyone,” Mourinho said when asked to explain his decision. “To punish anyone, I also need someone to punish me because we are a team. When we win we win together, when we lose we lose together.
“I made changes thinking about the characteristics of this game and this kid [McTominay] has a great desire to recover the ball. He's a kid that chases the ball, tries to recover high up the pitch and when he has the ball he plays always simple.
“Sometimes against opponents like Huddersfield, who play so close, with so many bodies, sometimes simplicity is genius. You have to open space by playing simple, so it was a decision to play the kid.”
Pogba, who appeared to have a touchline spat in the defeat to Tottenham before being substituted, eventually replaced Jesse Lingard in the 65th minute and Mourinho was pleased with his impact.
“Paul came on very well, with a great attitude, with spaces we had a the time, we were winning 1-0 and Paul could show talent, his qualities.
“I try to do what I think is best for the team in any moment,” he added, reiterating his defence of the decision.
“I prefer to look at it in the beautiful way of a little kid [McTominay] that arrived here at 9 years old with mum for the first training session. Ten or eleven years later he is playing in United shirt in important match in Premier League at home.
“I prefer to look at that perspective. Paul is a fantastic player, one of the most talented in the world, but to sit on the bench one day is not the end of the world.”
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