Stan Wawrinka Advances as Novak Djokovic Retires from Match, Daniil Medvedev Relishes the Boos, Reaches Final Eight of US Open (September 1, 2019) FLUSHING MEADOWS, NY - Former US Open champion Stan Wawrinka has reached the quarterfinals as No. 1 and defending champion Novak Djokovic was forced to retire with a left shoulder injury with the Swiss leading 6-4, 7-5, 2-1, “I … [Read more...] about Stan Wawrinka Advances as Novak Djokovic Retires from Match, Daniil Medvedev Relishes the Boos, Reaches Final Eight of US Open