Top-ranked Serena Williams will combine with Wimbledon doubles champion Jack Sock in the United States team which will compete in a star-studded Hopman Cup tournament in January. Williams won the Cup with James Blake in 2003 and Mardy Fish in 2008 and will again use the tournament as preparation for the first Grand Slam tournament of the season, the Australian Open. Read more http://espn.go.com/tennis/story/_/id/11621155/serena-williams-headlines-hopman-cup-field