It happened on October 7th 2010. Caroline Wozniacki became the new world number one, passing Serena Williams, Venus Williams, Kim Clijsters, Vera Zvonareva and Justine Henin.
Without a doubt, this is a water cooler story since the Danish player is yet to win a major. Even more stunning is the fact that she has managed to get to the top without having played in a Grand Slam final in 2010.
Wozniacki is ahead of Serena despite the American having won the Australian Open and Wimbledon. She is also ahead of Vera Zvonareva, who reached the Wimbledon and US Open finals, and Kim Clijsters, who has just won the US Open.
How in the world the 20-year-old from Denmark managed to become world number one despite all these facts I simply do not know.
The Dane has played by far the most tennis among the top 15 players. She has played 24 tournaments so far in 2010, while Venus has played 15, Serena 14, Clijsters 13, and Henin 10.
It is obvious that the WTA ranking system favours quantity instead of quality. It highlights those who play the most instead of those who focus primarily on majors.
We've already had Jelena Jankovic and Dinara Safina managing to reach the top without winning a Grand Slam. And now it's the turn of Wozniacki.
We have to take into account the fact that Caroline was unable to play her best in tournaments where the best players have entered. She is yet to prove she deserves this ranking.
Is this a big deal? I believe so.
It is not he first time we have had issues over the ranking account system. The same story happened with Jankovic and Safina, while Serena was still dominating women's tennis.
What is the fairest system? To become world number one by accumulating points over the whole season, or by playing the tournaments that everyone wants to win?
The 20-year-old Dane has taken advantage of players who restricted the number of tournaments they played over the course of the year. The ranking system would be different if Serena, Kim and Justine played more tournaments.
But their decision to limit the number or tournaments played is welcome news for decent payers such as Wozniacki, Elena Dementieva, or Zvonareva.
The first is the new world number one, while the second two will be doing battle to finish the season as the world number three.
However, I have to give Caroline credit for taking her chances. The ones Jankovic, Dementieva, and Victoria Azarenka have failed to take.
I like the fact that hard work and consistency are being rewarded and the Wozniacki family have been working on it for 15 years.
Piotr Wozniacki has managed to reach his goal. He began to train his daughter at a very young age with conviction, work ethic, structural methods, and intelligence.
Caroline demonstrates great values for sport, just like Rafael Nadal does on the men's side. Both are not only the symbol for natural talent, but instead their courage and personal involvement are the biggest assets we could expect from world number ones.
They are great ambassadors showing the real values of the sport.
It remains to be seen whether Wozniacki can remain at the top for a long time, or whether she will collapse the way Safina or Jankovic did.
But Caroline can only get better. She doesn't have a complete game, which is one of the reasons why she has never won a major.
The Dane's serve has improved, however her forehand is still weak. Therefore she doesn't have firepower when hitting her forehand and cannot mix up her shots too much. She has a great defence, can counter-punch very effectively but still gets in trouble when she needs to control the points. This is a positive sign if you consider she has become the world number one with many areas left to improve.
It will be interesting to see how fast she can improve since she knows how to work hard.
Caroline's main rivals for the top spot won't change their schedule. I can't see Serena or Kim playing for a full year anymore. The same goes for Venus and Justine. The American is suffering with her knees, while the Belgian is not consistent. I can only see Zvonareva being able to take her seat over the next two years.
And the other young players take more time than expected to bloom.
Azarenka's results have been disappointing; she is struggling with consistency. Agnieszka Radwanska doesn't possess too many assets, while Anastasia Pavlyuchenkova, Yanina Wickmayer, Dominika Cibulkova, Sorana Cirstea, and Petra Kvitova cannot consistently challenge Caroline.
They will need more time in order to be able to threaten the Dane. When they are ready, Wozniacki will have improved even more and will therefore be much tougher to beat.