This has been the year of the Big Three. No, I'm not talking about Roger Federer, Novak Djokovic, and Rafael Nadal. No, for the first time in years, the ATP is seeing more parity than the oft-ridiculed, oft-maligned WTA. This year the WTA has been ruled by three women -- Victoria Azarenka, Maria Sharapova and Serena Williams -- who have made their mark on three different surfaces -- hardcourts, clay, and grass, respectively -- and each of whom find themselves in the semifinals in the last Slam of the year.
Here's a preview of Friday's women's semifinals:
Victoria Azarenka  vs. Maria Sharapova  (Second match, Ashe): When the new WTA rankings are released on Monday these two women will sit on top, with Azarenka retaining her No. 1 with her semifinal run and Sharapova moving up a spot at No. 2 with hers. Until Serena Williams' resurgence over the summer, Azarenka and Sharapova were head and shoulders above the rest of the field, splitting the first two Slams of the year, facing off regularly in the finals of the largest tournaments, with Azarenka owning Sharapova on the hardcourts.
Sharapova has won just two of their six meetings on hardcourts, and both of those were three-set affairs back in 2009. Since then, Azarenka hasn't dropped a set to the Russian on concrete, reeling off four straight wins on the surface in blowout fashion, none more famous than her 6-3, 6-0 win in the Australian Open final this year. These are the types of losses that can get inside your head, and much like Sharapova's inability to get past Serena, it's hard not to wonder if she has a similar problem developing against Azarenka.
The mismatch didn't start as a mental thing, though by my eyes Sharapova sure doesn't like being compared to Azarenka in any way. Two Nike-sponsored blondes from the former Soviet Union who moved to the States at a young age, trained in America, and grab headlines as much for their whooping and shrieking as their blistering backhands. So yeah, any comparisons are totally off-base, Maria.
Take away their superficial similarities and these two offer a subtle tactical contrast that seems to neatly explain Azarenka's dominance on hardcourts and, in return, Sharapova's ownage on clay. Much of Azarenka's success comes from her ability to hug the baseline, take the ball early, and take time away from her opponents. Sure, that's the mindset for most players in the modern game, but what Azarenka is able to do is get the ball with pace and placement better than anyone else -- think Novak Djokovic with a headband. Crush the ball deep? Vika will send it back at your feet to beg a short ball that she can crush. Lather, rinse, repeat.
That's where the Sharapova matchup breaks down. Azarenka is able to quietly -- well, not quietly, per se -- exploit Sharapova's movement, preventing her from getting a full load to unleash on her groundstrokes. What Sharapova needs to do is put the pressure back on Azarenka by returning serve well. The problem is, Sharapova has not served or returned particularly well in their hardcourt matchups, surprising given Azarenka isn't exactly known for blowing serves past her opponents. Against Sam Stosur, Azarenka never got her serve above 100 mph, even if she makes up for it in placement.
This is the best rivalry going on in women's tennis right now. Sharapova has done her best to squirm out from under Vika's thumb, even if for a brief moment, though the jabs have been more verbal than racket-based. She's gone out of her way to throw shade the Belorussian's way, whether sarcastically remarking on Azarenka's excuse of being injured in her loss in the Stuttgart final, or taking a potshot at Azarenka's complaints about the WTA schedule. Sharapova may own Azarenka off-court -- her jabs really have been priceless -- but Azarenka owns her on hardcourt. Another high-profile loss for Sharapova at a Slam and I have no doubt Azarenka will be wagging her tongue and finger at the end of this one.
My pick: Azarenka def. Sharapova in three sets.
Serena Williams  vs. Sara Errani  (Third match, Ashe): Let's get the perfunctory compliments out of the way. No one would have thought Sara Errani, long considered a doubles specialist, would make one Slam semifinal, let alone two in one year. But she has transformed herself in 2012 thanks to a racket change and renewed focus on fitness. Undoubtedly inspired by her countrywomen Flavia Pennetta (the first Italian woman in the top 10) and Francesca Schiavone (first Italian woman to win a Slam), Errani dominated the second tier clay tournaments over the summer and broke open her bracket here in New York with a strong and smart performance to upset No. 6 seed Angelique Kerber in the fourth round. With four singles titles and seven more in doubles, this has been a career year for Errani.
So I'd love to give Errani a fighting chance here in the semis. But there's the whole thing about her opponent. Serena has yet to drop a set in the tournament, has dropped the fewest number of games through five matches, and is carrying a 24-1 record since her devastating first round loss at the French Open. So yeah, I just don't see it.
This has mismatch written all over it. A week and a half ago in New Haven, Errani took an ugly 6-1, 6-3 loss to another big hitter, Petra Kvitova. The Italian just could not get enough pace or depth on her shots to bother Kvitova, who was cracking winners at will. Barring an epic collapse from Serena, the same will happen here. The best Errani can hope for is that she can move the ball around the court and vary up the pace to keep Serena off balance. The problem with that tactic? While Serena's footwork can get lazy at times, she hasn't shown any signs of it during this tournament. Her movement and balance has looked as good as it's ever been. My pick: Williams def. Errani in two sets.