On Wednesday, Frenchman Ugo Humbert tested positive for Covid-19 in a pre-departure test after his first-round defeat to compatriot Richard Gasquet.
“A lot of players had it when they arrived, I think quite a few players have it now,” Zverev told reporters after his second-round win against John Millman.
“We’re not being tested, so I think if we were to be tested, in a sense there would probably be more positives than there are now.”
All players must be fully vaccinated to play at the Australian Open unless they have a valid medical clearance.
In an interview with Nine Network on Thursday, Craig Tiley, head of Tennis Australia, said players should be tested as soon as they arrived in Australia and again between five and seven days after their arrival.
He added that tests are mandatory if a player has symptoms of Covid-19.
DailyExpertNews has contacted Tennis Australia about testing protocols at the Australian Open, but has not received a response.
Garbiñe Muguruza, the women’s third seed, said after her second-round defeat to Alize Cornet that she tested alone in her hotel room every two days, while Zverev also said he had taken extra precautions.
“There are many cases in Melbourne, there are many cases in Australia everywhere, so I don’t do much outside. I haven’t been to restaurants, I haven’t been out, I haven’t been anywhere but the hotel room and the courts,” he said.
“I kind of do a bubble for myself, simply because I don’t want to take any risks and give myself the best possible chance to do well here. If I get Covid, of course that’s not going to happen.”
According to Victoria’s Chief Health Officer Brett Sutton, the state registered 21,966 new cases of Covid-19 on Wednesday, making a total of 246,894 active cases.
The Australian Open will conclude on January 31.
