Jose Mourinho is never shy to publicly criticise his players.And the Portuguese manager was at it again as his interview with Univision became public knowledge in England.When addressing United's young players, Mourinho said that they lack maturity and courage.He then went on to name drop Luke Shaw, Anthony Martial, Jesse Lingard and Marcus Rashford."They’re lacking maturity,” he said, per the Guardian. "For example, Luke Shaw. When I got here two years ago, the boy didn’t even know how to compete. Great potential, yes, but he doesn’t know how to compete."And when we talk about Luke Shaw, about Martial, about Lingard, about Marcus Rashford, we’re talking about boys with great potential but who still are lacking – a word I can’t say but you like to say a lot – having that [courage]. They’re lacking a bit of this.”Mourinho then went on to call the youth in England 'spoiled kids' and saying they lacked character and personality.Of course, his comments have not gone down well.Man United were in action against Crystal Palace on Saturday and went on to labour to a disappointing 0-0 draw.Rio Ferdinand was on punditry duty for BT Sport during the day and, despite not watching United's draw, he could not resist having a pop at Mourinho for the comments."When you get comments that come out of the club in a press conference or an interview that he done in the week where he's hammering four or five of the young players at the club, saying their mentality isn't right, what do you expect?" he said."Do you expect to have players on your side or do you expect your players to go 'hold on a minute, my manager is hammering me in public again'."I just don't think it's right for a football manager to be doing that."I don't think you're going to get productivity out of those kind of comments. I don't think it's proactive for the club."What he's said, that might be true. He's behind closed doors, he sees these boys day in, day out."He might look at those 4 or 5 kids and go, 'you know what, this is exactly how I feel about you'. He's got that right to say that."But I think behind closed doors, in the changing room embarrass them in front of the team."You don't get positivity doing that publicly and the fans don't like that either."

Rio's right - if Mourinho wants to have a go at his players, he should be doing it behind closed doors.

Absolutely no benefit is going to come from him criticising them in public.

Realistically, the only impact it's going to have is a negative one and not just the players in question will get upset, United fans will too.

Mourinho also risks alienating his squad if he has a go at them all one by one.

It's about time he started complimenting his players in public rather than slating them.