Pogba has deputised as skipper in the absence of club captain Antonio Valencia on three occasions this season against Leicester and Brighton in the Premier League and a Champions League trip to Young Boys.
Pogba criticized Mourinho for a lack of attacking football in United's 1-1 draw against Wolves.More news: 6 siblings of Arizona GOP congressman endorse his opponent
Pogba was faulty for the Wolves' equaliser after losing possession in midfield.
He questioned Pogba's attitude and told his squad at the club's Carrington training base that the Frenchman does not represent what a captain should be.
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And so it was that United should end the regulation time of their cup clash against Frank Lampard's impressive side with the Stretford End appealing for their team to "Attack, attack, attack" in much the same way that Pogba had wanted to see more.
The 25-year-old attacking midfielder spent four years in Turin where he established himself as one of the best midfield players in the world.
The red card which inevitably followed brought Lee Grant into action for the first time as a United player and with five minutes to play he was picking the ball out of his net as Jack Marriott smartly followed in Mount's initial shot to turn home what appeared likely to be a victor.More news: Sergio Agüero signs one-year Manchester City contract extension to 2021
The defeat isn't the only issue as it's the manner of the defeat with Manchester United failing to press on after Juan Mata grabbed an early goal for the team. We had the personality to take penalties and play the way we did.