NO. 1 ON THE LINE: The season-ending Barclays ATP World Tour Finals is headlined by eight players from as many countries. This is the first time since the 1974 Masters in Melbourne the year-end championship features eight players from eight different countries. New No. 1 Andy Murray is trying to finish the season as the top player in the Emirates ATP Rankings for the first time while reigning four-time champion Novak Djokovic is attempting to regain the top spot and end the year No. 1 for the third season in a row and fifth in six years. This is the eighth year the season finale is being held at The O2 and this will be the third time in the...