With Serena Williams Out, WTA Finals Offer Peek at the Future. Tennis, Clarey, Christopher, Williams, Serena, Women's Tennis Assn, Azarenka, Victoria, Cibulkova, Dominika, Davenport, Lindsay, Kerber, Angelique, Keys, Madison, Muguruza, Garbine, Pliskova, Karolina, Radwanska, Agnieszka, Sharapova, Maria, Simon, Steve (1955- ), Singapore