The 25-year-old joined United's youth team at the age of 16 in 2009, but left for Serie A team, Juventus, in 2012 - the year before Ferguson stepped down at Old Trafford.
Ferguson's former assistant and former England manager, Steve McClaren, says that United's previous manager would have got the best out of the Frenchman.
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He said: "For Pogba, leaving Manchester United and Sir Alex Ferguson has not done him any good. Coming back to that environment should improve him."
Comparing Pogba with rival Manchester City's De Bruyne, McClaren said: "De Bruyne looks like he has gone away to Germany for three or four years, come back and matured - he is consistent and is becoming a top player.
"Pogba looks like he has come back after leaving Manchester United and has not matured, he is inconsistent."
However, he added that current United manager Jose Mourinho could still improve the midfielder, with patience and discipline.
He said: "I think [Jose] Mourinho is the perfect manager to make him consistent and mature.
"With top players you need patience, but he [Mourinho] needs to drive him [Pogba] and discipline him. Everything that De Bruyne is, that is what he should be.
"It is not about age, it is about experience. De Bruyne is mature now but he still looks young. Pogba hasn't got that maturity in his game. Mourinho is trying to get that back and he is trying to get discipline and hard work."
The comments follow claims made by City boss Pep Guardiola at his pre-match press-conference on Friday, that Pogba was offered to him by agent Mino Raiola during January;s transfer window.
United face their rivals City in the Manchester derby on Saturday, which if they win, City will seal their expected Premier League victory to become the earliest ever title winners.
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