There will be eight different Grand Slam finalists this year, so women's tennis is as wide open as it's been in decades. History says someone will emerge to take over from Serena Williams, but who that will be isn't at all clear.
The upset bug just kept biting and biting and biting in the women's draw at the US Open. And while there are two former Grand Slam champions remaining in the final eight, the other six are itching to get a breakthrough. Get to know the contenders.
The time is now for Petra Kvitova, Eugenie Bouchard and Simona Halep. And they know it. With Serena Williams' mysterious slip, the rising stars have battled their way into Grand Slam finals and made the sport all the more compelling.
The top three women's seeds have been vanquished, thanks to Agnieszka Radwanska's brilliant upset of No. 2 Victoria Azarenka on Wednesday, but those remaining are playing compelling tennis heading into the semifinals.