Serena Williams was in pain “acceptable” pain, her coach called it after rolling her right ankle during the second set of a US Open victory.
Defending champion Novak Djokovic is out of the US Open after quitting because of injury against Swiss 23rd seed Stan Wawrinka as defeat loomed in an electrifying fourth-round match.
Djokovic, 32, retired with a shoulder problem seconds after a double fault left him two sets and a break down۔
Three-time Grand Slam champion Wawrinka had dominated the last-16 contest in a boisterous atmosphere at Arthur Ashe Stadium, producing a powerful display reminiscent of his best to lead 6-4 7-5 2-0, when Djokovic decided he could not continue.
Djokovic’s withdrawal failed to take the shine off a breathtaking performance from Wawrinka, who earned his biggest victory since beating Britain’s Andy Murray, then world number one, in the 2017 French Open semi-finals.