Whenever Serena Williams is out of a big tournament, the entire tennis world takes note. Often, there is almost an asterisk next to the tournament and the winner because, "Serena was not there."
Here at Bleacher Report, we also have articles mourning Serena's absence and speculating whether it will hurt the event and the legitimacy of the winner.
And while there can be no doubt that Serena Williams is the best female player of the last decade, it's harder to claim that she's been in a league of her own for the past couple of years, partly due to her many injuries and long absences from the game.
On the other hand, we have Kim Clijsters.
She was the World No. 1 for a couple of weeks in February and was the dominant player on tour from September 2010 till her injuries put her out of the game.
She's mostly been absent from the game since March due to multiple injuries—shoulder, ankle and stomach—and has missed the last two slams plus the WTA Championships in Istanbul (for which she didn't qualify because of her injuries).
The last slam she did play, the French Open, she lost in the second round after a two-month injury layoff.
Yet, prior to the US Open, the big story wasn't that two-time defending champion Kim Clijsters was not there to defend her crown. Serena was back and was winning tournaments, so there was no need for an asterisk.
Serena was the big favourite and there was no reason to ask, "Who isn't here?"
At the WTA Championships in Istanbul, Clijsters was again the defending champion yet the attention primarily went to Serena Williams, who also didn't qualify because of injuries.
To be fair, Serena Williams produces great drama and great stories. She is a champion and she is the best player of the last decade by a considerable margin.
But Kim Clijsters has been the best female hard-court player since she returned to the tour in the summer of 2009.
Better than Serena?
Based on their records, most certainly yes.
Clijsters has won four of the five biggest hard court tournaments she's participated in since returning: the US Open (2009), the US Open (2010), the WTA Championships (2010) and the Australian Open (2011).
The only blemish on an otherwise perfect hard-court resume is her 2010 Australian Open loss.
By comparison, Williams has won the 2009 WTA Championships and the 2010 Australian Open, but lost at the 2009 and 2011 US Open.
As for her record against Serena, they've only met once since Clijsters returned to tour in an infamous US Open semifinal in 2009. Clijsters won.
Given that Clijsters has won the vast majority of the biggest hard-court tournaments she's been participating in since she returned to tour, she has earned the right to be missed as much as, if not more than Williams, particularly when both are absent from the big hard-court tournaments.
Both of them are scheduled to return to the WTA tour at Brisbane in early January. Sam Stosur and Maria Sharapova are among others in the field and I presume defending champion and rising star Petra Kvitova will be as well.
That should give us an early indication of whom to count on in Australia. Hopefully the rising stars get to face both Serena and Kim.