Shoulder injury stops top-seeded and defending champion Novak Djokovic as No. 23 seed Stan Wawrinka reaches the quarterfinals for the second year in a row.
Stan Wawrinka advances as injury fells defending US Open champ Novak Djokovic
Shoulder injury stops top-seeded and defending champion Novak Djokovic as No. 23 seed Stan Wawrinka reaches the quarterfinals for the second year in a row.
