Serena Williams has accepted a wildcard entry into the Western and Southern Open, having failed to defend her Olympic titles at Rio 2016.
Williams won gold in the women's singles and doubles at London 2012, but, alongside sister Venus, suffered a first-round defeat to Czech duo Lucie Safarova and Barbora Strycova before being beaten by Elina Svitolina in the third round of the singles event in Brazil.
The world number one and two-time defending champion has subsequently entered the tournament in Cincinnati and will be the top seed for the competition.
"We are thrilled Serena is returning to defend her titles. She is a fan favourite wherever she goes, especially here in Cincinnati as the reigning champion," said tournament director Andre Silva.
Williams finished as runner-up in 2013 before overcoming Ana Ivanovic and Simona Halep in successive years to lift the title.
The competition gets underway on August 13, with Williams in the hunt for her 24th title at Premier level.