Isner will be playing in front of a home crowd in Atlanta from Friday to Sunday, with a limited number of fans allowed to attend subject to temperature checks on arrival.
Seating will be “social distancing compliant”, the website states, while masks are not required but are available to use.
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Isner’s tweet promoting the event saw responses highlight the surge in coronavirus cases in Georgia, with the USA – the worst-hit country – seeing a spike in the past week.
Isner said he is promoting the sport in a “safe manner”, with extra scrutiny on tennis tournaments following the Covid-19 outbreak at the Adria Tour which saw World No 1 Novak Djokovic among the players testing positive.
“You coronabros can stay in your basement all you want. I choose to live my life and play/promote the sport I love in a safe manner,” Isner said.
Tennis reporter Ben Rothenberg called plans to welcome hundreds of fans to the event “crazy”, adding: “Holding a tennis event for the public in a city under siege just feels out of touch with the stark reality.”
Isner responded to Rothenberg, calling the “spooky headlines” factually incorrect, and doubling down on the tournament’s safety protocols.
He replied: “Ben, your concerns are valid, but, as someone who covers our sport for a living it would be nice if you would be supportive of WTT and Atlanta with their efforts to put on safe events instead of posting spooky headlines like this one that are factually incorrect.”

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