Paul Pogba, Jose Mourinho need to pull together at Manchester United - Bryan Robson

Jose Mourinho and Paul Pogba must put their differences aside and pull together in order to get Manchester United back on track, former captain Bryan Robson has told ESPN FC.

United have suffered two defeats from their opening four matches, with reports of a falling out between Mourinho and Pogba continuing to the dominate the headlines -- and the midfielder was strongly linked with a move to Barcelona.

Pogba was made captain for the opening match of the season against Leicester, but following that clash, he refused the opportunity to end talk of his unhappiness, stating: "There are things and there are things that I cannot say otherwise I will get fined."

But Robson insists it is important that the pair put their differences to one side and focus on the team's goals.

"Within a football club you've all got to get on well together," he told ESPN FC. "You don't have to be friends but, after getting off to a slow start, that's the time when you all pull together."

Robson also believes United's players need to take more responsibility by finding ways to get the best out of each other -- whether by confrontation or encouraging one another.

"You've got to have belief in your teammates and in yourself," he added. "You've got to start raising your own game.

"It's not all about having a go at people, it's about encouraging your teammates as well. That's really important for me in football that, as teammates, you've got a responsibility in the dressing room to have a go at each other if you think somebody is being lazy or slacking in training.

"If somebody's been brilliant, you praise them. You try to then get more out of them."

Fresh from a World Cup victory, much was expected from Pogba this season, but his performances have come in for criticism due in part to United's underwhelming start.

Yet Robson believes the Frenchman has the club's DNA, having joined the academy in 2009 at a time when some of their most successful players were there. And he insists the 25-year-old is often the subject of unfair criticism.

"He came through the ranks when the Class of 92 were there," Robson said. "He knows what it takes to be a Manchester United player.

"There is a little bit of unfair criticism for me about Paul. Every time Manchester United don't play well and get a poor result, it always seems to be Paul who gets most of the criticism.

"If I just look at one game this season when we were really poor, our worst game of the season -- against Brighton -- there were a lot of other players who have to take responsibility. Not just Paul."