Over recent years in the Premier League, we have seen so many talented young players who have graced us with their immense ability and goalscoring talents, but none more so than Cristiano Ronaldo. 

At the tender age of 17-years-old, and a mere two weeks after impressing football scouts worldwide with his performance in a friendly against Manchester United, the Portuguese youngster was signed by Sir Alex Ferguson for a fee of around £12.2m.

This deal was scheduled to happen 12 months later, but after his performance alerted the presence of AC Milan, Juventus and Real Madrid, Sir Alex knew he needed to act quickly in order to bring this mesmerising talent to the Premier League.

After asking for his former shirt number 28, Ronaldo was given the iconic number seven shirt at Old Trafford, and he quickly learned what this number meant to the fans. Their heroes such as George Best, Bryan Robson, Eric Cantona and David Beckham had worn this short over the years and gained many fans utmost respect through brilliant performances and great goals. Ronaldo knew he had to adapt instantly to the Barclays Premier League.

In August 2003, Ferguson handed the fragile youngster his debut as a substitute against Bolton Wanderers, where for 30 minutes he dazzled fans and defenders alike with his quick-feet and silky skills, and became an instant hit.

Although Ronaldo would soon realise that the Premier League was not all about tricks and skill, and after several harsh fouls and lunges which left him with scars and bruises to his legs, he would soon understand that he needs to be a lot more physically demanding on the pitch and become the main focal point of their attacks.

Fast forward to 2006, Ronaldo was now a first-team regular at Old Trafford, having already featured in over 100 matches. He was now twice the player he was back in 2003, and most notable his sheer physical shape had totally changed: he was bigger, stronger, and faster than ever before.

He had also worked harder on his footwork and passing ability, ready to terrorise defenders once again. The boy was now a man and this was down to pure determination and many days of practice on the training ground.

His outstanding technical ability caught the attention of everybody during the season of 2006-07, and his free-kicks were now something to be admired. He had got the whole world wondering how he made the ball dip and swerve multiple times in the air, confusing goalkeepers all across the Premier League and Europe - this was a skill that many footballers have tried, and they have all failed to replicate. 

Ronaldo played 53 matches during the season of 2006-07, scoring an impressive 23 goals from midfield, ranging from free-kicks and penalties, to long-range goals and headers. He was becoming the full package, a real force in world football.

His personal honours for the season included 'PFA Players' Player of the Year', 'PFA Young Players' Player of the Year' 'PFA Fans' Player of the Year' and 'FWA Footballer of the Year award' thus becoming the first ever player to win all four major trophies.

Ronaldo was now being named as one of the best players in the world, by many football fans around the globe, and in his 2007-08 season with Manchester United we saw the Portuguese sensation firing an all cylinders.

He netted a total of 42 goals in all competitions, including 31 in the Premier League which saw him finish the league as top goalscorer. He was named 'Champions League best forward' and 'Champions League Player of the Tournament', as well as finishing as the top scorer with eight goals.

Later in 2008, Cristiano Ronaldo would be named the Ballon d'Or winner, after finishing second the previous year to a certain Lionel Messi. This had caught the serious attention of Spanish giants, Real Madrid, who were a long awaited dream of Cristiano's - and he made it no secret he would love to play for such an illustrious club if they came in with an offer.

Reports suggested Ronaldo asked Ferguson if he could leave Old Trafford, and sign for his boyhood dream team Real Madrid, but Ferguson convinced Ronaldo to stay for another 12 months.

Many fans believed Ronaldo would under-perform during the 2008-09 season due to his links with Real Madrid, and feared he may not put in his best performances. They were wrong. Cristiano continued to give it his all for the club, finishing the season with a goal every two matches, a very impressive stat for someone who wants to leave the club.

The highlight of his season was his stunning 40-yard goal in the quarter-finals of the Champions League, later claiming it to be "the best goal I have ever scored" and also becoming the first ever player to win the 'FIFA Puskas Award' for the best goal of the year.

In June 2009, Manchester United accepted an outrageous bid of £80m from Real Madrid, and Ronaldo had received his wish to leave and join the Spanish club.

Ronaldo had won three Premier League trophies, two League Cups, one Champions League winners' medal, one FA Cup, one FA Community Shield and a FIFA Club World Cup trophy. Memories he will never forget, at a club which drew the real potential from such a fragile, but promising young individual.

In conclusion, during his very impressive six-year stint at Manchester United, we saw a young teenage kid, mature, grow, and evolve into the most expensive football player the word has ever seen. A true indication of the pure talent and ability which he possesses.