NEW YORK, NY, USA - The upsets kept coming at the US Open on Saturday, as Petra Kvitova - who had a shot at becoming the World No.1 after this tournament and who was the No.3 seed - fell to unheralded Serbian qualifier Aleksandra Krunic in a third round match on Louis Armstrong Stadium.
Coming into the US Open, Krunic had never beaten anyone in the Top 10 - in fact she had never even beaten anyone in the Top 70 - she changed all that in a dramatic second round victory over No.27 seed Madison Keys, but could a No.145-ranked qualifier really do any damage against a World No.4?
Meanwhile, that World No.4 had a lot on the line - Kvitova would have become World No.1 by winning the title and Serena Williams falling before the quarterfinals, and this was also her opportunity to finally go deep at the US Open, the only Grand Slam she had never been to the quarterfinals of.
The Turning Point
Lifted by what was already her best Grand Slam performance, Krunic threw everything at Kvitova throughout the match, from big serves and pinpoint passing shots to high balls, slices and drop shots, and after closing out a tight 41-minute first set, she broke again early in the second set, eventually finding herself up 6-4, 4-2, and on the verge of another massive upset in Flushing Meadows.
Kvitova - a two-time Grand Slam champion at Wimbledon - showed some major signs of a comeback from there, winning two games to tie the second set at 4-all. But Krunic broke one last time and stepped up to the line and served the match out, finishing the match with one last marathon rally, scrapping her way past all of Kvitova's blasts and drawing one last unforced error to clinch it, 6-4, 6-4.
By The Numbers
It was a high quality match - that last forehand error was the only thing that put Kvitova into the negatives in terms of winners-to-unforced error differential, as she finished at -1 (33 to 34). Krunic was just too clean and consistent in the match though, finishing with a +3 differential (17 to 14).
The biggest number of the day, though, was 141 - the difference between Kvitova and Krunic's WTA Rankings of No.4 and No.145, and a perfect indicator of the sheer magnitude of the upset.
A beaming Krunic was interviewed on the court afterwards by WTA legend Mary Joe Fernandez.
"First of all, I want to say thank you to everyone here for your support," Krunic said. "I didn't expect you would all be cheering for me as much as you did today. It was an amazing atmosphere out here.
"It was an honor for me to be on the same court with Petra. She's a great champion and I watched both of her finals at Wimbledon. To play against such a champion meant I had to give my all on the court and be here as long as possible. But I was just hoping to win a set, I didn't expect to win!"
The Serb, who is through to the second week of a Grand Slam for the first time in her career, was asked about what was going through her mind as she stepped up to serve for the match at 6-4, 5-4.
"In the back of your mind you have thoughts like don't miss the serve, and don't make the double fault, but I just tried to keep those thoughts somewhere far away today," she answered.