Despite the ranking disparity between the two players, this wasn't exactly the upset that it might seem like on paper.
Wozniacki is obviously one of the best players on the planet, but it is the Russian that has been playing the better tennis since Wozniacki won the Australian Open in January.
Since then, Kasatkina has made it to the semifinal at the St. Petersburg Open and the final of the Dubai Tennis Championships. The 20-year-old also happened to have played Wozniacki in the quarterfinals of that run in St. Petersburg. She won that match 7-6 (3), 6-3.
Kasatkina vs. Wozniacki match point and post-match interview:
For Kastatkina, this was yet another victory that should help to continue building the youngster's confidence. Talent has never been her issue, so it's good to see her putting things together mentally.
One of the x-factors in this match was Wozniacki's inability to win on her second serve. The world No. 2 was just 8-for-28 on second-serve points won, and that is simply not good enough when playing against a player like Kasatkina.
The problem for Wozniacki is that this tournament was an important one for her. Wozniacki won this event back in 2011, so it was reasonable for her to expect a deep run this year. The early loss will, however, make it hard for her to regain her No. 1 ranking from Simona Halep in the near future. Halep is still going strong in Indian Wells, as she won her fourth-round match against Qiang Wang on Tuesday.
Kasatkina, meanwhile, has to be feeling like she can beat anybody right now. She is swinging the racquet really well and it wouldn't be surprising if she continues to rise in the rankings moving forward.
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