Brisbane: Australian World Number one Ash Barty on Thursday pulled out of the US Open as she doesn't want to risk travelling during the coronavirus pandemic.
The 24-year-old Australian is the highest-profile player so far to opt-out of the August 31-September 13 Grand Slam tournament in New York because of the global health crisis.
"My team and I have decided that we won't be travelling to the ... Western & Southern Open and the US Open this year," Barty said in a statement.
"I love both events so this was a difficult decision, but there are still significant risks involved due to COVID-19 and I don't feel comfortable putting my team and I in that position.
"I wish the USTA all the best for the tournaments and I look forward to being back in the US next year."
Barty is yet to decide if she'll defend the French Open title she won last year for her breakthrough singles major. The clay-court Grand Slam event was postponed earlier in the year and rescheduled to start September 27, after the US Open.
Australia's closed international borders would make it difficult for Barty to travel during the pandemic. Technically, Barty would have to receive permission from the government to travel abroad, and flight options are limited. Upon returning to Australia, travelers face a mandatory two weeks in quarantine.
Other players have expressed concern about travelling to the US, where more than 150,000 people have died from COVID-19.
Barty had to make her decision because entries were open for the Western & Southern Open, which is scheduled for August 20-28 and was moved to the same hard courts at the Billie Jean King National Tennis Center that are slated to host the US Open.
Serena Williams, Coco Gauff, Novak Djokovic and Rafael Nadal were on Wednesday's initial entry lists but Barty, two-time Grand Slam champion Naomi Osaka and 2019 US Open champion Bianca Andreescu were not for the tournament moved from Cincinnati to Flushing Meadows.
Being on Wednesday's lists doesn't necessarily mean a player will compete at the tournament.
No sanctioned professional tennis events have been played since March because of the coronavirus. Both the women's and men's tours plan to return in August. The women's tour still aims to return next week at Palermo, Italy.