The women’s draw revolves around a familiar question: Which version of Serena Williams will show up? 

Serena Williams
If it’s the one who dispatched Angelique Kerber in vintage fashion at the Wimbledon final in July, she’s the overwhelming favorite. If it’s the one who looked out of sorts in a crushing early-round loss at the Olympics—possibly struggling with a shoulder injury—well, she’s still the favorite, but a more modest one. 

Even if Serena isn’t quite in peak form, there remains a second familiar question: Who will challenge her? Spaniard Garbiñe Muguruza seemed up to the physical and mental task when she beat Serena to win the French Open this year, and she is no doubt a threat in Flushing Meadows. But she crashed out early at Wimbledon before being drubbed by eventual gold medalist and pride of Puerto Rico Mónica Puig at the Olympics. (The two may face each other again in the third round of the Open, which could settle whether the formerly obscure Puig can leverage her Olympic momentum.) Fifth-seeded Romanian Simona Halep has looked impressive in recent months, and seems poised to leap into the true elite. And there’s younger talent, like the 21-year-old American Madison Keys, who has been creeping up the rankings. But the most credible challenger is No. 2 seed and newly minted silver medalist Angelique Kerber, who, with a title, could take over the number 1 ranking from Serena after more than 180 weeks. 

Last year at the Open, Serena was under a microscope, needing to win the tournament to capture a rare calendar Grand Slam—and she lost, shockingly, in the semifinals. This year, the stakes aren’t exactly low: She’s playing to retain her top ranking, and if she wins the tournament, she’ll surpass Steffi Graf’s record 22 Grand Slams. But the spotlight has dimmed, however slightly, which may mean a more tranquil Serena. If she plays relaxed tennis, and if her shoulder isn’t bothering her too much, there’s no doubt that she remains the best in the world.

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