Serena Williams lost the world No. 1 ranking on a double fault

Serena Williams fell in straight sets to 24-year-old Karolina Pliskova in the U.S. Open semifinal on Thursday night, 6-2, 7-6. The loss marks the second consecutive year in which Williams falls in the semis at the U.S. Open, and ends her quest for a record-setting 23rd grand slam championship.

With the loss — which came, frustratingly, on a double fault down 5-6 in the tiebreaker — Williams also loses the world No. 1 ranking.

It’s hard to believe that Williams, who earlier this season reached the final of the Australian Open and French Open, and won Wimbledon, could somehow walk away from a semifinal loss with a lower ranking, and yet because of an even better season by Angelique Kerber, Kerber will take over as the new No. 1.

Earlier this season, Kerber beat Williams to win the Australian Open, and lost to her in the final at Wimbledon. Now she will play Caroline Wozniacki in the other semifinal at the US Open, having suddenly become the top player in the world.

Williams, meanwhile, ends her 2016 campaign with a disappointing effort against Pliskova. Playing her second match in as many nights, Williams looked out of sorts from the very first game — particularly when it came to cracking Kliskova’s big serve.

After a first set won by Pliskova in under 30 minutes, Williams battled in the second set but suffered from too many unforced errors. She began to limp during the tiebreaker, and quickly went down 3-0. After taking a 5-4 lead, it looked, at least for a moment, that Williams might steal the second set.

But she just wasn’t good enough for Pliskova, and a double fault to lose the match says it all.

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