Ever since the end of Serena Williams’s prime, women’s tennis has found itself in a strange period of unpredictability. It went from having an automatic favorite going into any Grand Slam tournament to suddenly having no idea who was going to win. 

The 21 major tournaments since Williams’s last triumph, at the 2017 Australian Open, have seen 14 different Grand Slam champions, including 12 first-timers. And at this U.S. Open, where seeded players are tumbling like empty cups in the stands, the women’s game is no closer to identifying a clear favorite. In fact, the draw is now so open that a plucky underdog from Compton, Calif., is beginning to think she might even make a run.