The Olympic champion suffered the injury while playing a charity touch rugby game in October 2017 and has not raced internationally since.
Having been in the background for most of his career, Molefi Ntseki admitted that it’s his greatest achievement to be named Bafana Bafana coach.
Swiss 23rd seed and 2016 champion Wawrinka led Djokovic 6-4, 7-5, 2-1 when the Serb quit, having received treatment on his troublesome left shoulder before the start of the third set.
Williams, a six-time US Open winner, romped to a 6-3, 6-4 victory over Croatian 22nd seed Petra Martic to set up a quarter-final with China's Wang Qiang, the conqueror of world number two Barty.
Tonga have been drawn with England, France, Argentina and the United States in Pool C, with only the top two teams to advance to the quarterfinals.
International Motoring Federation (FIA) race director Michael Masi said an investigation into the crash on Saturday that killed Formula Two driver Anthoine Hubert had already begun.
Harry Maguire said United must take their opportunities in front of goal if they are to keep up with their top four rivals.
Ntseki started out a school teacher before the coaching bug hit him and he followed his passion.
Thapelo Morena is nursing an injury while Darren Keet is finalising his work permit in Belgium, which requires him to stay in that country until all the paperwork is done.
Links arrived at the Citizens in January 2018 from Egyptian Premier League side Al Assiouty Sport.
