Hungarian Olympic bronze medallist Boglarka Kapas has announced on her Facebook page that she tested positive for the novel coronavirus.
She would have needed two negative tests to continue her training, the first test was negative but the second came out positive, reports Xinhua news agency.
"I am currently in quarantine for two weeks at home, I cannot leave the apartment. For now, I do not feel any symptoms," the 26-year-old swimmer informed on Tuesday, recalling the importance of protective measures against the outbreak and the significance of staying home.
Later, she told public television channel M1 that when she found out the result, she cried.
Kapas won a bronze medal at the 2016 Rio Olympics in the women's 800m freestyle event and last summer she won the 200m butterfly at the world championships in Gwangju, South Korea.
According to official figures, the number of confirmed coronavirus cases in Hungary stood at 492 on Tuesday, with 37 reported recoveries and 16 fatalities.
Meanwhile, Cruzeiro president Jose Dalai Rocha has said he is recovering well after becoming the third club official to be struck down by COVID-19.
CEO Sandro Gonzalez and board member Alexandre Faria had already tested positive for the virus before Rocha received news of his diagnosis on Tuesday.
Last week, former Turkey goalkeeper Rustu Recber, the country's most capped player, was in a "critical period" in hospital with coronavirus.
AC Milan and Italy legend Paolo Maldini and his son Daniel, who currently plays for the club, have both tested positive for coronavirus, the Serie A club had said in a statement earlier.
Juventus star Paulo Dybala also tested positive for coronavirus. The Argentine forward had become the third player from the club that has been diagnosed with the infection.