Simona Halep has been forced to withdraw from the Zhengzhou Open, which begins on Monday, September 9.

The WTA World No.4 exited the US Open at the hands of Taylor Townsend, who won their second-round match in New York, 2-6, 6-3, 7-6(4) in thrilling style.

READ MORE: How Andreescu’s coach ‘channeled’ her talent: ‘I noticed very early on that she was a born competitor’

Halep subsequently pulled out of the mixed doubles, in which she was slated to play with compatriot Horia Tecau and has been unable to recover sufficiently from injury to participate in China next week.

“I'm disappointed to withdraw from the Zhengzhou Open as I was looking forward to playing in a new city for the first time,” she said. “Unfortunately, I have been experiencing pain in my left ankle and my medical team has advised me it would be best not to play next week. I wish the tournament every success in its first year and hope to be back next year.”

The absence of the Wimbledon champion is of benefit to Tereza Martincova, the WTA World No.141, as she has joined Fiona Ferro, Jelena Ostapenko and Jasmine Paolini in being promoted to the main draw from the alternates list.

With the Czech now automatically qualified, it leaves two spots open for the qualifying draw, which must be filled at the sign-in deadline.

Halep had been expected to be the second-highest ranked player in the draw behind Karolina Pliskova. With seven Top 25 players participating, including Kiki Bertens, Elina Svitolina, Aryna Sabalenka and home favorite Wang Qiang, there remains impressive depth for the inaugural edition of the tournament.