She's won two of the last three Australian Open titles, but after an injury-filled year it seems that Victoria Azarenka's career is at a crossroads. It doesn't help matters that a tricky draw awaits in Melbourne.
For Serena Williams, a win in Sunday's US Open final would mean a place alongside legends Chris Evert and Martina Navratilova with 18 majors. For Caroline Wozniacki, a win would provide validation to her longtime reign as No. 1.
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.
So dramatic and scary was Serena Williams' exit from the Wimbledon doubles tournament last month that it was fair to wonder how she would respond at Stanford this week. She answered with her fourth WTA tour title of the season.
Ball's in your court, Serena Williams. Before the world No. 1 takes the court next week for the first time since her bizarre withdrawal from a Wimbledon doubles match, we have 10 questions we need answered.
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.