Madison Keys and Coco Vandeweghe both took their favored opponents (Agnieszka Radwanska and Maria Sharapova) to three sets, but both fell under the pressure. Serena lost the first set to Victoria Azarenka, but came back to win the second and is up a break in the third. She is well on her way to the semifinals where she will face Sharapova next.

Assuming Serena makes it to the Final, a potential match against Garbine Muguruza (Spain) would be interesting. Muguruza beat Serena last year in the French Open and took her to three sets earlier this year in the Australian Open. Serena has never lost to Radwanska (and hasn't lost to Sharapova since 2004, a string of 16 matches).