As the final curtain comes down on the season and transfer talk begins to heat up, attention turns towards some of world football's biggest names who may be angling for a move away from their current clubs.

Whether it is Raheem Sterling at Liverpool, Petr Cech being caught up in a rumoured tug-of-war between a number of Premier League heavyweights, or even David de Gea offered the ultimatum that it is now or never as far as a move to Real Madrid is concerned, every window has many drawn-out sagas.

Of course, each truly great transfer story must have certain key ingredients. The player must firstly be wanted by his current club; one or more suitors must make their interest known; a will-he won't-he element surrounds the situation for a good few months beforehand; and agents get involved, either hinting that a move is on the cards or merely trying to improve the player's bargaining power at their current club.

Each of these criteria were ticked off by one Cristiano Ronaldo, who after months - years even - of being linked with a move to Real Madrid, finally edged a huge step closer to achieving his dream by seeing a world-record fee agreed between Los Blancos and Manchester United.

The 2008 Ballon d'Or winner was craved by every team in world football, each wanting the man considered the best on the planet to lead their attack. Only one could truly afford the astronomical asking price, however, and that side just happened to be the one team Ronaldo fantasised about playing for as a youngster.

Even up until that point, on this day six years ago, the whole saga had plenty of back story. United had lodged a complaint with world governing body FIFA less than 12 months beforehand, citing a deliberate attempt by Real to lure their star player to the Bernabeu by unsettling him.

Real's interest may have quietened, but the story certainly did not. "Now I understand I made the best decision," the former Sporting Lisbon sensation told Spanish sports paper Marca. "I am with Manchester in body and soul." Except he was not. Red Devils boss Alex Ferguson hit out at the capital club a few months later, claiming that he would never sell a player to them.

However, on the back of another stellar personal campaign, which ended on a sour note when Barcelona claimed a 2-0 victory in the Champions League final, Madrid were soon back on the case. Having scored 118 goals in 292 appearances for United, Ronaldo was simply too talented - and marketable - to let him slip away from their grasp.

The return of Florentino Perez as Bernabeu president provided the last piece of the transfer jigsaw, as the man who helped assemble to world-famous Galacticos went about putting together a team of similar value. In came Kaka for what was then a world-record deal of £56m from AC Milan, just days before the Ronaldo bid was accepted. Kaka could hold claim to being the most valuable player on the planet for less than a week.

"United have agreed to give Real Madrid permission to talk to the player," a statement on the Premier League outfit's website read, adding that the Portuguese had once more expressed a desire to leave. The worldwide media went into overdrive, with Marca describing the impending switch as "the signing of the century".

Elsewhere across Europe, the press were less understanding. Italy's Gazzetta dello Sport led with: "That's not fair. Mad Real. After Kaka, Real Madrid sign Cristiano Ronaldo." French publication L'Equipe, on the other hand, simply opted for: "Benzema's turn?"

For Ronaldo himself, the offer on the table was said to be worth in the region of £180,000 a week, which was thought to be second only to Kaka's bloated wages. He was officially unveiled as a player on July 6 in front of joyous supporters, but the debate over whether United were right to let him leave still rumbles on. Many suggest they had little choice, others believe that he should have remained for another year at the very least.

The 30-year-old recently carved his name in Madrid folklore by joining Raul and Alfredo di Stefano in scoring 300 goals for the famous club. Ronaldo reached the landmark figure in just 287 games - a goalscoring rate he has continued right up until the end of the current season, with an astronomical 48 goals in La Liga alone.

De Gea's impending move to the Spanish capital may be wrapped up in the coming days, but it will not come quite as close as reaching the transfer saga heights that Ronaldo set when finally seeing his dream move to the Bernabeu become a reality in 2009.