What Serena Williams' Loss to Karolina Pliskova Means for Australian Open 2017

Serena Williams couldn't follow up her Wimbledon conquest with a victory at the U.S. Open, losing to Karolina Pliskova in the semifinal in New York on Thursday.

But this latest disappointment, coupled with a poor showing at the Rio Olympics, has folks questioning if Williams is losing her dominant grip over the women's game.

Williams has been competitive this season. She went 33-5 with two single titles in 2016 coming into Thursday's match, per the WTA's official website. She was the runner-up at both the Australian and French Opens. Few players strike more fear into the hearts of opponents than she does.

But heading into next season, it's hard to ignore that Williams has appeared vulnerable at times this season. Between Wimbledon 2012 and Wimbledon 2015, she won a whopping eight of 13 possible Grand Slam titles. She was one of the most dominant athletes in all of sport. 

Maintaining that level of play was always going to be difficult. But when a player goes from such startling dominance to a more realistic form like the one she's shown at times in 2016, it's fair to question if she's come back down to earth for good.

It's also hard to ignore that Williams is 34. At some point, she's going to slow down. Perhaps it's already happening.

And the game's top contenders outside of Williams—Pliskova, Garbine Muguruza, Agnieszka Radwanska, Angelique Kerber, Simona Halep and Victoria Azarenka, to name a few—have to sense vulnerability in Williams' game. Muguruza and Kerber can attest to that firsthand, having beaten her in the French and Australian Open finals, respectively.

But it's probably not time to write off Williams just yet. She's won six titles in Australia, after all. And she'll be fueled by all of the talk that her game is perhaps declining. 

So assuming her decline is a dangerous game to play. But recognizing the potential signs of decline?

That's becoming easier to do.

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