It is understood the midfielder then bit back at the Red Devils boss in a dressing room row that took place in front of the entire team.
The visitors went behind early on against Southampton, conceding twice in 20 minutes at St Mary’s stadium.
But the visitors rallied back with goals from Romelu Lukaku and Ander Herrera in a first half that saw four goals.
It seemed as though United would go on to win the game but their display in the second half was flat and uninspiring.
Jose Mourinho reportedly gave Paul Pogba a dressing down at full-time
At one point, cameras were on Mourinho when Pogba lost the ball by attempting a fancy flick. The United boss responded to the sloppy play by throwing his arms in the air and shouting angrily from the dugout.
According to the Daily Record , Mourinho gave the 26-year-old a major dressing down in the away changing room at full-time.
A source from the dressing room has claimed Mourinho called Pogba “a virus” and told him he showed a lack of respect toward his team-mates and fans with the nature of his performance.
The World Cup winner is said to have hit back at his boss and replied: “You don’t play. You don’t respect players and supporters. And you kill the mentality of the good honest people around you.”
Mourinho was critical of United’s midfield at full-time. When asked why his side struggled against Southampton, he told BT Sport: “I think because we lost so many balls in midfield. We lost so many balls in the last third it was difficult to have that continuity.
“I think that was the only reason.
“What we did so well in the last 15-20 minutes of the first half was to connect with the attacking players by transporting the ball, leaving the ball in the right moment, the right choice of pass, playing simple, accelerating the game.
“The second half we went back to that dynamic, again, of where we lose too many balls in midfield.
“And the players don’t understand that simplicity is genius, especially in some parts of the pitch. They keep and keep and keep going to complicated football and it is difficult to have that continuity.