Cristiano Ronaldo became one of the world's best players during his time at Manchester United.

Signing for the club as a relatively unknown teenager in 2003, the Portuguese international would soon establish himself as one of the very best players in the world.

After winning almost everything there was to achieve at the club, Ronaldo would eventually leave Manchester for Real Madrid in the summer of 2009.

It's actually 10 years ago today that Real Madrid and United agreed an £80m fee for Ronaldo.

He would officially leave a few weeks later and the number seven shirt was passed over to Michael Owen.

But, the shirt has become cursed since then.

Owen would go on to have a poor time at Man United. 

Other than scoring a dramatic late winner against Manchester City, his time was an unpleasant one riddled with injuries.

He would score just five times in the Premier League before leaving the club in 2012.

The next three players to wear the famous number seven shirt did not fare much better.

Antonio Valencia, Angel Di Maria and Memphis Depay would all wear the shirt, but would combine for just six Premier League goals in 90 appearances.

It was hoped Alexis Sanchez would break the curse when he was signed from Arsenal in January 2018.

But, he too has failed to live up to expectations.

The Chilean forward has played 32 times in the league for United and scored just three goals.

It has been a major decline for Sanchez, who was averaging 15 goals a season in the Premier League for Arsenal.

So, in total, United's number sevens have scored just 15 Premier League goals.

For Cristiano Ronaldo, it's been a different story.

The Portuguese forward managed to score 33 goals in his first season in La Liga, more than double what Man United's number 7s have racked up in the past decade.

And since leaving United Ronaldo has managed 332 league goals. That's just 317 more than what Man United's number 7s have achieved in the same time frame.

Oh how United fans will wish he never left...