Serena Williams has exited the Wuhan Open at the second round after being forced to retire from her match against Alize Cornet.
The world number one had enjoyed the brighter start to the match, breaking Cornet's serve in the opening game.
Cornet responded with a break of her own in the sixth game to level the scores, and both players failed to hold serve in the five games that followed.
However, Williams began to feel unwell and she withdrew from the match while leading the first set 6-5.
Cornet, who has now beaten the American for the third time in succession, will face Kirsten Flipkens or Jarmila Gajdosova in the next round.
