Dawn Harper Nelson finished out of the medals at the IAAF World Championships in Moscow last year, placing fourth behind Brianna Rollins, Sally Pearson and Tiffany Porter. But the 30-year-old US athlete stands on top of the world list in the 100m hurdles in 2014 with the 12.44 she clocked at the IAAF Diamond League meeting in Paris in July.
Harper Nelson, the 2008 Olympic champion and 2012 Olympic silver medallist, will start the clear favourite in her Americas team vest – ahead of Porter, who will be representing Europe.
Born and raised in the United States but a British athlete since 2011, Porter followed her world outdoor bronze in 2013 by taking world indoor bronze in Sopot in March and has since claimed Commonwealth silver and European bronze in the 2014 outdoor season. Her season’s best is 12.63.
Simon Turnbull for the IAAF