By Ann Liguori
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Karolina Pliskova, the big server from the Czech Republic, pulled off the biggest upset of this year's US Open and of her career.
At the expense of Serena Williams, of all people.
The 6-foot-1 Pliskova won 84 percent of the points on her first serve on her way to a stunning 6-2, 7-6 (5) victory over the 22-time Grand Slam singles champion on Thursday night.
Pliskova smashed seven aces and 19 winners, overall. For a 24-year-old playing in her first major semifinal, she maintained her composure and nerves despite the enormity of the situation. She was facing an opponent many consider one of the greatest female athletes of all-time, on center stage and in prime time.
The 10th seed not only defeated the six-time US Open champ, but also bounced Williams out of the No. 1 spot in the world rankings, a position she had held for 186 consecutive weeks. Angelique Kerber, who defeated Caroline Wozniacki in Thursday's second semifinal, took over the top spot.
It was Serena's second straight loss in the US Open semifinals. Last year, Roberta Vinci beat her, preventing Williams from achieving a historic calender Grand Slam.
Earlier in the week, Pliskova knocked Serena's older sister, Venus, out in the fourth round in three sets.
As impressive as Pliskova looked, Williams was flat from the start. She was a step slow. And in the second set, a left knee injury, which she later revealed she injured in the second or third round, became an issue, as she could hardly move to get to some shots. At various points late in the second set, it almost looked like she was ready to retire from the match.
Serena was asked after the match what part of her game was most affected by her hobbled leg.
"Mental, because when you're hampered you're thinking of other things," she answered.
When a reporter asked her if she felt worn out after winning a three-setter in the quarterfinals on Wednesday afternoon, less than 24 hours earlier, Serena snapped.
"Okay, I'm not going to repeat myself. I wasn't tired from yesterday's match. I'm a professional player; been playing for over 20 years. If I can't turn it around after 24 hours and play again then I shouldn't be on tour," she said. "So I definitely wasn't tired from yesterday's match at all. It wasn't a five-hour match. I have practiced three hours, so it wasn't that huge of a deal."
But Serena looked tired from the start, both physically and mentally. She's human. And she's about to turn 35. It takes longer for one's body to recuperate at that age, even if you're Serena Williams.
We're accustomed to seeing Serena dig herself out of holes. But physically, she looked fatigued early and was hobbled later. Whereas Pliskova looked as fresh as could be and used her lethal serve to her advantage.
Serena will continue to face serious challenges as she attempts to add to her Grand Slam trophy case. Will her body cooperate? Can she stay injury-free? Will she want to tolerate the stress? Will she show more vulnerability?
With 22 Grand Slam singles titles, Serena is currently tied with Steffi Graf, two behind all-time leader Margaret Court. Can Serena win three more to grab that record?
I think so. She hates to lose. She's a perfectionist.
But a lot will depend on injuries. And as long as she avoids serious ailments and continues to have the passion to work hard and handle the pressure, she'll have a chance to set the ultimate record.
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