Love him or hate him, Jose Mourinho is one of the greatest managers in history.

The self-proclaimed 'Special One' burst onto the scene by winning the treble with FC Porto in 2004 before transitioning effortlessly to Premier League football with Chelsea. And now, naturally, he takes residence at arguably the world's biggest club - Manchester United.

That's not to mention his wildly successful spell with Inter Milan and his solid, albeit eventually disastrous, second tenure at Stamford Bridge.

There's perhaps one spell in his career that Mourinho will have a few regrets over and that would be his time at Real Madrid. 

Although the Portuguese enjoyed a rampant La Liga victory in 2012, his first Clasico ended in a 5-0 bludgeoning, he never reaped Champions League success and his final season was dogged by fallings out.

One of those arguments came with Cristiano Ronaldo.

A source told Goal.com in 2013: "Their relationship was one of complicity - they spoke very little in their three years together at Madrid."

For all the tumultuous events of their off-pitch relationship, though, they never failed to deliver on the pitch together, even other teammates fell short. 

And when Mourinho was asked who he thought should win the 2012 Ballon d'Or, he delivered an insight into his incredible footballing brain that he tends to keep off limits now, with an inspired speech on Ronaldo and Messi.

He explained: "It would be a crime for Cristiano to not win the Ballon d'Or. And I keep saying it's harder to be Cristiano than Lionel Messi. 

"I'll tell you: Messi grew up in the team he plays for now; with the teammates he plays with now. Cristiano came from England to a team that was losing. He had to grow up in the past two years with this team in construction.

"One plays centre forward and the other is a winger. Messi is about 50 metres closer to the goal and has less defensive work.

"How can a winger score the same amount of goals as a centre forward does? 

"This is a winger that defends, a winger that ends the game in the 94th minute with a sprint to chase Pedro in a goal scoring position. This is a player that, in dead ball situations, comes 20 times to the defensive area.

"He is very important to the defensive set up. He is a player that isn't protected by nothing or nobody. It's much, much harder." 

You can see footage of the speech on YouTube, here.

Mourinho was also keen to call out the very nature of the Ballon d'Or competition and posed the question: "If they are equal [Messi and Ronaldo], is it normal that one wins four and the other just one? No. It's normal for one to win three and the other two.

"If Cristiano doesn't win, it's because he isn't very kind, he doesn't sell his image well or give apologetic interviews."

An anomalously lengthily interview reply from Mourinho and what a result...

Who do you think is the greatest player of all time? Have your say in the comments section below.