By JOHN PYE, AP Sports Writer

BRISBANE, Australia (AP) — Ash Barty has joined the ranks of high-profile players concerned over the staging of the U.S. Open while there’s still so much uncertainty around the coronavirus pandemic.

The women’s No. 1 hasn’t had the chance yet to defend her French Open title because all elite tennis competition is shuttered. She’s already processed the fact there’ll be no Wimbledon in 2020 but is still awaiting clarity on the U.S. Open, which is scheduled to begin Aug. 31.

Novak Djokovic and Rafael Nadal, winners of the last eight men’s major titles, have aired reservations about the potential restrictions on players, limits on player entourages and other changes being considered for the U.S. Open. Women’s No. 2 Simona Halep reportedly is also uncertain about playing.

“I have concerns too,” Barty said in an e-mail to The Associated Press. “I understand the tournaments are eager to run but keeping everyone safe has to be the priority.”

A decision from the U.S. Tennis Association’s board about whether to hold the Grand Slam tournament in New York in August could be made as early as this week. The U.S. has accounted for more than 115,000 of the almost 433,000 deaths globally from COVID-19, including more than 30,000 in the state of New York, according to data compiled by Johns Hopkins University.

Djokovic last week told Serbia’s state broadcaster RTS that most players he’s talked to “were quite negative” about entering the U.S. Open and that for him, “as things stand, most probably the season will continue on clay at the beginning of September.”

The French Open was postponed from a May start to late September because of the COVID-19 outbreak. Under usual circumstances, the U.S. Open is the last of the four majors to be played in the season, when the tours go back to hard courts following the grass and clay-court swings.

U.S. Open tournament director Stacey Allaster has said organizers have been trying to figure out how to “engage fans virtually,” making it unlikely that fans — or at least large groups of fans — will be allowed to attend.

Under proposals to get the tournament started, players would need to prove they had tested negative for COVID-19 before traveling on charter flights the USTA would organize from a handful of cities. There would likely be daily health questionnaires and temperature checks, along with occasional nasal, saliva or antibody testing.

Barty said she’s “still getting my head around what the tournament set up would be.” Australia closed its international borders in March and there’s still travel restrictions domestically and strict physical distancing regulations, although restrictions are easing. Australia has recorded 102 deaths from 7,335 cases of COVID-19, but the infection rate is declining.

“I can’t wait to get back out there and play but we have to make sure it’s safe to do so first, not just for me but for my team,” Barty told the AP.

Barty hasn’t played competitively since a semifinal loss to Petra Kvitova at the Qatar Open in late February. That followed her first title on home soil at the Adelaide International in January and her semifinal run at the Australian Open.

She’s been able to spend time at home in Australia’s Queensland state since March, keeping up tennis practice and fitness while also lowering her golf handicap during regular rounds with her partner Garry Kissick, a trainee golf pro. She had a 24th birthday during the height of the lockdown in April, and hosted a virtual party on Zoom earlier this month to mark the first anniversary of her first major singles title at Roland Garros.

A Grand Slam title defense is likely a priority for the remainder of the year, but there’s so much unknown.

“It’s tough to set goals, that’s for sure, (when) we still don’t really know what the rest of the year will look like, there is so much out of our control.,” Barty said. ”When we have some certainty on the rest of the year, my team and I will sit down and set a few tennis goals.”

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