She is the latest woman with a Grand Slam title or high ranking to withdraw from the tournament that begins next week amid the coronavirus pandemic.
Six of the top eight women in the WTA rankings already are out, including No. 1 Ash Barty, the reigning champion at Roland Garros, and No. 6 Bianca Andreescu, the 2019 winner at Flushing Meadows.
Withdrawal of Ostapenko and Spain’s Cara Suarez Navarro gave Kurumi Nara and Whitney Osuigwe an entry into the main draw.
US Open Tennis : 6 of top 8 Women tennis players have withdrawn from US Open 2020
Reigning US Open champion Bianca Andreescu of Canada, who ousted Bencic in last year’s US Open semi-finals, also declared last week she will not play in New York, joining men’s 2019 winner Rafael Nadal in skipping the tournament.
– World No. 1 Ash Barty (Australia) – Withdrawn
– World No. 2 Simona Halep (ROM) – Withdrawn
– World No. 5 Elina Svitolina (UKR) – Withdrawn
– World No. 6 Bianca Andreescu (CAN) – Withdrawn
– World No. 7 Kiki Bertens (NED) – Withdrawn
– World No. 8 Belinda Bencic (SUI) – Withdrawn
Serena Williams, seeking a 24th career Grand Slam title to match Margaret Court’s all-time record, will compete at the US Open, as will men’s world number one Novak Djokovic.
New York was one of the hardest-hit US cities when COVID-19 first spiked in March and April, a temporary hospital even being established on indoor courts at the US Tennis Center.