A lot of defenders have tried - and failed - to stop Cristiano Ronaldo during his career.

Whoever Ronaldo faces, he always seems to get the better of them.

But who is the toughest opponent Ronaldo has faced during his incredible career?

That question was put to Cristiano last year. His answer? Ashley Cole.

"Over the years I had some great battles with Ashley Cole, he does not give you a second to breathe," Ronaldo told Coach Mag.

"He was such a tenacious player when he was at his peak, quick, tough in the tackle. You knew it would never be an easy game."

But do you remember the first time Ronaldo faced Cole?

No?

Well, we’ve found a clip of the first time they met - and it didn’t take long for Ronaldo to humiliate Cole.

The clash between United and Arsenal in September 2003 will always be remembered for Ruud van Nistelrooy’s late penalty miss and the carnage that ensued afterward.

But it was during that match that an 18-year-old Ronaldo proved that he was the real deal.

Just weeks earlier, Ronaldo stunned everyone during his debut against Bolton which Alex Ferguson described it was “unbelievable.”

While performing against Bolton is one thing, producing an impressive display against the league’s top sides is another thing altogether.

And after just four minutes, Ronaldo had Cole on his backside.

A brilliant stopover and a quick change of pace left Cole struggling to change direction, causing him to slip over.

Watch: Ronaldo's impressive display vs Arsenal

Take a look at Ronaldo’s skill - and the rest of his highlights during the 0-0 draw:

Fourteen years on, and Ronaldo has established himself as one of the best players to have ever played the sport.

The Real Madrid superstar is set to win his fifth Ballon d’Or in January to draw level with Lionel Messi’s tally.

At the age of 32 and defenders are still trying to work out how to stop him.