The newly installed tournament favourite is in action on Monday, and Abelson Info discuss whether or not there could be more upsets on the way...
"Even though Halep has been installed as the favourite for this one, Jankovic has been a consistent presence in the latter stages of tournament for some time but will want to push on here"
Sunday saw the biggest shock of the tournament thus far, as world number one and tournament favourite Serena Williams crashed out at the hands of Ana Ivanovic.
Her exit undoubtedly opens up the top half of the draw, but the impact on the other half will see the likes of Victoria Azarenka and Maria Sharapova realise that their chances of reaching the final and winning have just improved.
Azarenka arguably faces the toughest fourth round match, as she prepares to take on 13th seed Sloane Stephens who has dropped just one set over the past week.
However, the Belarusian ace has yet to surrender a set at all, and will be further buoyed by the fact that she defeated her American rival when they met in the semi-finals of last year's tournament.
Stephens was unable to really compete in that clash, with Azarenka winning in straight sets and dropping just five games en route to making her second consecutive final.
Nevertheless, she won't take this one lightly as the 20-year-old has all the skills to provide a threat to her bid of making it a hat-trick of Australian Open titles.
With Williams no longer a problem, the world number two won't be the only player relieved, as Sharapova's dire record against her old foe goes out the window and she will now be targeting another Grand Slam.
However, given that she is still working her way back to her best she will not be looking any further ahead than her next opponent, Dominika Cibulkova.
After her marathon win over Karin Knapp in the second round, the Russian star simplified things last time out against Alize Cornet and will be confident of producing a similar performance.
Sharapova won their last meeting which came at Wimbledon in 2011, but narrowly leads Cibulkova 3-2 in their head-to-head record and will still have bad memories of being dismantled in their quarter-finals clash at the French Open in 2009.
The Slovakian has caused Sharapova problems in the past, and will be confident of doing the same on Monday. While it is unlikely that the third seed will falter at this point, it could be more than a competitive game.
Jelena Jankovic will be hopeful of facing her in the next round, but first she must overcome the challenge of Simona Halep.
With just three places in the world rankings separating these two, Halep has won last their two meetings although both have come on clay while Jankovic won a three-set battle in their only clash on this surface.
However, even though the Romanian ace has been installed as the favourite for this one, Jankovic has been a consistent presence in the latter stages of tournament but will want to push on.
As a result back her to prevail, while Agnieszka Radwanska will finally end what has been a thrilling and memorable winning streak for Garbine Muguruza, although the Spaniard won't go without a fight.
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