What does it take to become the greatest player in the world for the best part of 10 years?

Of course, it takes a lot of skill but you need more than just the ability to play football.

Just ask Cristiano Ronaldo.

The Real Madrid superstar has been one of the best players in world football for a decade, winning four Ballon d’Ors in the process.

He’s scored an incredible 399 goals in 390 appearances for Los Blancos over the past eight seasons since his move from Manchester United.

But it wasn’t necessarily obvious that he was destined for greatness when he first joined United.

The Portugal international arrived at Old Trafford as an 18-year-old for a little over £12 million as he became the most expensive teenager in English football history.

When we first saw him in England, Ronaldo was a ‘show pony’. Constant stepovers, constant diving and very little end product.

However, things soon changed for Ronaldo as he emerged as an incredible talent.

But how did he go from potential superstar to one of the best players in the world?

Ferdinand on what sets Ronaldo apart

Well, former United teammate Rio Ferdinand explains how Ronaldo worked hard to fine tune his game and revealed its his mentality and desire that sets him apart from any other player.

"He was very young, he was very inexperienced, very immature in the way he played, a bit of a show pony at times," Ferdinand said, per the Mirror.

"But he had the mentality, he had the desire, the work ethic.

"He always wanted to be a superstar but the difference is he worked beyond anyone to become a superstar, and that's what sets him apart."

Now, as a 32-year-old, Ronaldo is on the brink of his greatest season to date. While winning the Champions League and the European Championships for Madrid and Portugal, as well as the Ballon D'or in 2016 it was regarded as his best calendar year to date.

However, in 2017 he could lead his side to their first La Liga title since 2012 while helping them defend the Champions League - something that has never been done before.

If he does that, then surely a fifth Ballon d'Or will be his.