Top-ranked Serena Williams will team with John Isner to represent the United States in a star-studded field at the Hopman Cup international tournament in January. Williams and Isner will join the Serbian pair of Novak Djokovic and Ana Ivanovic, Belgium's Justine Henin, Australia's Lleyton Hewitt and France's Gael Monfils in the mixed teams tournament which runs Jan. More...