For the second straight year, Serena Williams was upset in the US Open semifinals.
Whereas the American was defeated by crafty veteran Roberta Vinci 12 months ago to end hopes of a rare calendar-year slam, an ailing Williams lost to big-hitting Karolina Pliskova 6-2 7-6 (7-5) on Thursday in New York.
She'll thus have to wait to become the first player in the Open Era to win 23 majors. Williams is currently tied with Steffi Graf on 22.
And in a double blow, when the new rankings are released Monday, the 34-year-old will lose top spot to Angelique Kerber, ending Williams' record-tying with Graf 186th straight week at No. 1.
It certainly wasn't vintage Williams about 24 hours after she outlasted Simona Halep in a slugfest and she told reporters post match Thursday she was dealing with a left-knee injury.
It would explain some of her unusual statistics against Pliskova, who plays Kerber in Saturday's finale. Knowing she locked down the No. 1 ranking even before her match started against Caroline Wozniacki, the German appeared bolstered and downed Williams' good friend 6-4 6-3.
"It's just incredible," the Australian Open winner and Olympic silver medalist told the crowd on Arthur Ashe stadium. "To be here in the final for the first time means a lot. And to be No. 1 in the world, it sounds amazing."
Serving impeccably through the quarters, Williams, meanwhile, slumped to five aces and six double faults. Williams had averaged 12 aces per match in the tournament prior to the last four and struck 18 against Halep.
Williams, too, committed 31 unforced errors, erring on routine looking forehands and second serve returns.
"Yeah, I have been having some serious left knee problems," said Williams. "I wasn't tired. Fatigue had absolutely nothing to do with it. If I was tired I should definitely get into a new career.
"I wasn't able to move the way I wanted to move. When you're injured you're thinking of other things when you should be just playing and thinking of your shots. My mind was just a little bit everywhere. But it was what it was."
She suspected the injury surfaced in the second round. The nature of the contest against Halep might have made things considerably worse.
"I was making errors that I never make, and definitely I didn't make in this tournament in particular," said Williams. "So many simple, simple shots that I easily could have made."
Williams, however, praised Pliskova, who played a flawless first set and ultimately held her nerve. Pliskova's booming serve shone, particularly in the first set.
"Karolina played great today," said Williams. "I think if she had played any less then maybe I would have had a chance.
"So I think I wasn't at 100%, but I also think she played well. She deserved to win today."