Following the 2016 US Open, Angelique Kerber replaced Serena Williams as the ruling player on the women’s singles circuit. Ten months later, she suffered a similar defeat to Serena. On Monday, when the WTA rankings change after the Wimbledon updates, either Karolina Pliskova or Simona Halep will be the new WTA queen. For Kerber, the struggle might not be over yet as the US Open Series includes few more thousand points that need to be defended. With so little space to grow, Kerber will have to maintain her status by matching last year's results.

It's a difficult task judging by her lack of success throughout the ongoing season.

Garbine Muguruza edged Kerber in three highly-competitive sets

Fighting for a place in the women's singles quarterfinals, Angelique Kerber and Garbine Muguruza delivered a consistent game of tennis. Both sides produced some of their best tennis. The German took the opening set and was in front in the second. From that point on, the resilience Muguruza displayed eventually paid off. She managed to push the set in a third decisive act where she edged Kerber by 6-4. In the end, the scoreboard had Muguruza winning by 6-4 4-6 4-6.

Their early collision is just another hint of how much dynamism tennis has these days.

It was the clash between the runners-up of the last two editions. Serena Williams is the one who surpassed them in consecutive years. Muguruza was the victim of the2015 final while Kerber lost at the last edition. While the German will step off the stage in order to assess her status, 2016 French Open champion Muguruza moves forward and will face Svetlana Kuznetsova next.

Kerber's exit creates a vacuum at the top

At the beginning of the tournament, the race for the world no. 1 spot was set to be a three-player battle. Karolina Pliskova was the subject of a major upset, losing in the second round to Magdalena Rybarikova who is the brightest surprise of these Championships. She will fight for a place in the semis against Coco Vandeweghe.

Still, at this time, Pliskova has the no. 1 spot in her pocket. For the situation to remain the same, Simona Halep must not reach the semis. The Romanian will face Johanna Konta in today's blockbuster.

For the second time in less than a month, Halep will be playing with the no. 1 spot on the table. The last time she had that opportunity she failed in a stunning way in the French Open final losing to Jelena Ostapenko. The funny thing is that Halep and Ostapenko might share the stage in the semis. The 20-year-old star is facing Venus Williams for a slot in the last four stages.