Stephens to join Isner on US Hopman Cup team
The 20-year-old Stephens, who upset Serena Williams in the Australian Open quarterfinals to start 2013, has improved 26 places in the rankings to No. 12 this year.
Under the competition format, eight teams are split into two groups for matches including men's and women's singles and mixed doubles. The winners of each round-robin group advance to a final.
Copyright 2013 by The Associated Press
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