Jose Mourinho has appeared to land a well-aimed dig at his successor as Manchester United manager, Ole Gunnar Solskjaer, with the suggestion that nice guy managers end up becoming puppets.

Solskjaer was initially praised for lifting the dark clouds that had engulfed Old Trafford during the final weeks of Mourinho’s reign, only to end the season arguing the club needed precisely the sort of dressing room overhaul that the Portuguese had called for before he was sacked.

Mourinho has already taken a very deliberate swipe at two of his fiercest critics, Paul Scholes and Gary Neville, since leaving Manchester, claiming they did not have the strength of character to cope in management and has now seemingly turned his fire on Solskjaer after United’s season rapidly disintegrated under the Norwegian.

United won just two of their last nine league games under Solskjaer, who initially did well with his positive and upbeat manner, and finished sixth, outside the Champions League positions.

"Generally, the players can feel a certain erosion, especially when you ask a lot of them,” Mourinho told L'Equipe. “When I say that the second season [when United finished as runners up to Man City] was fantastic, I say it because the potential and the objectives were met.

View more!

"I really squeezed, like an orange, to achieve them. When you have a very professional group of players who are ambitious, hard-working and talented, at a structured club, you don't have that erosion.

"When you are almost alone, in that you don't have the support of the club close to you, while certain players go somewhat against the coach, who is the nice guy?

"I don't want to be the nice guy, because the nice guy, after three months, is a puppet and that doesn't end well.

"I said nine or 10 months ago that after winning eight championships, finishing second with United may have been my greatest achievement. Now people understand.

"About United I want to say only two things: One is that time has spoken. Two is that the problems are still there."

Many of Mourinho complaints about the attitude and commitment of some players at United have been vindicated since he left – although he conveniently ignores that he signed many of the worst offenders.

The Portuguese had also demanded a new centre-back last summer, but his attempts to force the United hierarchy to buy one failed during a fractious summer tour of the USA. Solskjaer is now also desperate to improve his options in that area.

Mourinho has never been afraid to answer his critics and has also cut Scholes and Neville down to size since losing his job at United in December.

View more!

Scholes lasted just 31 days as manager at Oldham Athletic, before resigning with just one win to his name, while Neville famously failed in his time as coach of La Liga outfit Valencia - often remembered for a 7-0 hammering at Barcelona – before making a successful return as a pundit with Sky Sports.

Mourinho told Russian Television last month: “There is one part of it [management] that people sometimes forget, even some top pundits, they forget it, which is you have to be born with some talent adapted.

“It’s a little bit the same thing as what football academies can make with players I think it’s a natural knowledge and understanding of the game. Leadership qualities, communication qualities, emotional intelligence.

“It’s another thing that technology, experience at other levels can’t replicate, which is the knowledge of the pressure you are under. One thing is us, in front of a screen analysing a game live, and saying, ‘now I would take this one, and I would put that one.’

“That decision, when you are on the touchline, can you on the touchline have the same state of mind to be calm, to be an analyst, to read the game, to be brave enough to take the pressure?

“I used to say this, everybody in the world knows more about football than us…we have even in England, former top players, amazing in front of the screen, they go to football clubs, and after two months, goodbye, let’s go home because this is not right for us. So there are things you have it, or you don’t have it.”