Tuesday 16 August 2016 09:14, UK
Serena Williams has withdrawn from this week's Western & Southern Open in Cincinnati, citing a shoulder injury.
The world No 1, who crashed out of the Rio Olympics in the third round, is the WTA tournament's two-time defending champion.
The shoulder injury also caused Williams to pull out of the Rogers Cup in Montreal last month.
"I'm very disappointed I'm not able to compete in the Western & Southern Open in Cincinnati as I was really looking forward to defending my title," Williams said in a statement on the tournament's website.
"My shoulder inflammation continues to be a challenge, but I am anxious to return to the court as soon as possible."
Williams had accepted a wild card into the tournament and will now be replaced in the draw by Misaki Doi of Japan.
W&S Open tournament director Andre Silva said: "While we were excited that Serena had accepted a wild card to play in the event, we understand that health is her number one priority.
"It will only contribute to her longevity and the chance for our fans to see her in Cincinnati for many more years."
