Later tonight, the last of the women’s quarterfinal berths will be decided when Agnieszka Radwanska faces Garbine Muguruza.  For now, check out a series of takeaways from the earlier matches. 

Déjà vu all over again:  For the second straight day, a former Australian Open champion and title contender exited to a heavy underdog after winning the first set.  The first set looked more or less like business as usual for Sharapova despite shaky moments towards the end.  Then, the tide turned completely as Cibulkova broke serve six times in the last two sets as she dropped just five games.  Like Serena a day before, Sharapova was visibly hampered by an injury that required treatment between the second and third sets.  Like Ivanovic a day before, Cibulkova still deserved credit for closing out the match convincingly despite her opponent’s physical woes.  Those two champions have wobbled through many ugly victories against women who lacked the belief to capitalize on opportunities.  By contrast, the Serb and the Slovak proved themselves made of sterner stuff.

Pocket rocket:  Through the first week, Cibulkova recorded the most dominant victories of any woman.  The question remained whether it was a mirage, considering the indifferent quality of her opponents, but today she showed otherwise.  The Slovak struck an outstanding balance between control and aggression throughout the later stages of the match, when it grew clear that Sharapova lacked full strength. Those situations can be difficult to manage tactically, but Cibulkova generally chose the right moments to pull the trigger or to extend the rally in search of another opportunity.  She now has reached at least the quarterfinals at every major.

Aftershocks:  Two-time defending champion Victoria Azarenka already was favored to win the title after Serena’s loss yesterday.  But Azarenka’s route to a three-peat grew even smoother when Sharapova fell.  She is the only player remaining in her half who has reached an Australian Open final, and she is the only woman anywhere in the draw who has won a hard-court major.  Azarenka will attempt to become the first woman to claim three straight Australian Open titles since Martina Hingis achieved the feat in 1997-99.  With three rounds to go, though, a tournament full of surprises might hold more of them in store.

New year, same story:  Controversial medical time-outs or not, Victoria Azarenka always will be a difficult matchup for Sloane Stephens.  Azarenka simply does everything better, except perhaps serve.  She yielded a string of double faults in this match but will have found few other causes for regret in a well-rounded effort.  Finding her way into plenty of games on both players’ serves, Stephens did not lack chances to make this match more intriguing than it was.  The gulf separating them in experience played almost as large a role as the talent gap between them, for Azarenka won the vast majority of the key points without leaving her comfort zone.  

Silver linings:  Despite the deflating loss, Stephens largely rose to the occasion in this tournament overall.  Her fifth straight appearance in the second week of a major provides her with experience for which there is no substitute.  Coach Paul Annacone will feel encouraged by the way that his charge competed today, for the scoreline did not do justice to her effort.  Under relentless pressure on her serve, Stephens patiently stayed the course when many young players might have unraveled, and she showed an improved sense of point construction.  She could not sustain the combination of power and placement on point after point  needed to outmaneuver Azarenka, but that is a very tall task.  The game that Stephens produced today would have troubled most opponents outside the top 10 and some inside it.  

A second first-timer:  The coming-out party of Eugenie Bouchard unfolded the previous night, and the coming-out party of Simona Halep unfolded under the Melbourne sun today.  Like Bouchard, Halep did not reach her first major quarterfinal without suspense.  The match more than once seemed on the verge of slipping away from her.  In the first set, an early lead evaporated, and a second-set swoon gave Jelena Jankovic all of the momentum heading into the third set.  Despite her lack of exposure to this spotlight, Halep stopped the veteran Serb in her tracks and reeled off an emphatic bagel to punch her ticket to an intriguing date with Cibulkova.  She might even be favored in that match of two small women who throw punches far harder than their sizes suggest.

One Serb up, one Serb down:  As they rose to fame, Ana Ivanovic and Jankovic seemed to trace parallel trajectories.  Then, they traced roughly parallel trajectories as they tumbled down from those dizzying heights.  When Ivanovic broke through so spectacularly against Serena Williams, one wondered whether a similar breakthrough awaited Jankovic.  It was not to be.  Although she enjoyed an outstanding fall season that revitalized her career, Jankovic could not parlay that momentum (and a higher seed) into a deep Melbourne run.  With a winnable quarterfinal ahead, this was an opportunity squandered to reclaim more of her reputation and morale.  It was disappointing that someone who once showed such an appetite for competition could not muster a more resilient last stand than her limp third set.