'Shouldn't have played': Alexander Zverev in French Open virus furore

German Alexander Zverev has said he played with fever and breathing difficulties during his fourth-round French Open defeat to Italian teenager Jannik Sinner on Sunday, raising questions about the COVID-19 protocols at the clay-court Grand Slam.

Zverev appeared to be in discomfort and was seen coughing on court during the match, and called for the doctor and trainer.

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The French tennis federation (FFT), who run the tournament, told Reuters Zverev was most recently tested for COVID-19 on September 29 and the test returned a negative result the following day.

Zverev, 23, was up to date with his testing and was notified to undergo a routine test on Sunday, the day of his fourth-round match, the organisers added.

Organisers said Zverev did not consult with the Roland Garros medical service before his match against Sinner.

Zverev said he had been ill since his third-round win against Italian Marco Cecchinato on Friday and had a body temperature of 38 degrees Celsius.

"It was nothing wrong but I am completely sick after the match with Cecchinato in the night. Yeah, what can I say? I'm completely sick," a masked Zverev said during his virtual post-match news conference.

"I can't really breathe, as you can hear by my voice. I had fever, you know, as well. It was 38. It was 38 in the night or in the evening."

French government guidelines state that a person with COVID-19 symptoms - a body temperature above 38degC, a cough, sore throat, headache, muscle ache, loss of smell or taste - needs to isolate for seven days and immediately make an appointment for a test.

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The 23-year-old Zverev also played in Novak Djokovic's Adria Tour event in the Balkans where multiple players, including the Serbian world No.1, contracted the virus.

"To be honest, I warmed up today. I shouldn't have played," Zverev said after losing 6-3 6-3 4-6 6-3 to Sinner.

Asked if he was concerned that he might get sick, 19-year-old Italian Sinner said: "He's not positive or whatever. We have got tested quite many times, and obviously we were not that nearby.

"It's like we always had the distance. I don't think that I will have fever in the next days, or I hope so."

Tournament organisers said that two players in the junior girls' tournament had tested positive for COVID-19 and had been removed from the draw.

In total, approximately 3,000 tests have been carried out since September 17, organisers said.

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