McClaren also says Pogba was wrong to leave United for Juventus back in 2012.
"De Bruyne looks like he has gone away to Germany for three or four years, come back and matured," said ex-United No2 McClaren, while appearing as a pundit for Sky Sports.
"He is consistent and is becoming a top player and a complete midfield player.
"Pogba looks like he has come back after leaving Manchester United and has not matured, he is inconsistent but I think Mourinho is 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.
"De Bruyne is a great player but he is also plays for the team and works hard, tackles, win his duels, creates and scores."