Wimbledon champion Simona Halep retired from the Wuhan Open after sustaining a lower back injury in her third-round match against Elena Rybakina in China.
The world number six, who ended the year as world number one in 2017 and 2018, withdrew when trailing 5-4 in the first set against the Kazakh wildcard.
Meanwhile, Australian top seed Ashleigh Barty qualified for the quarter finals with a 6-3 7-5 win against Sofia Kenin. Read more