Past champs and future stars: catch the next champion of the @botwclassic in Stanford as the #USOpenSeries continues this Monday. Give us a 🙌 if you're ready to see the WTA stars in action! 🎥: @serenawilliams @angie.kerber @jokonta91 @domicibulkova _ #tennis #wta #instatennis #stanford #botwc #serenawilliams #angiekerber #johannakonta #dominikacibulkova