Two players have been withdrawn from the Australian Open qualifying tournament in Doha after returning positive Covid-19 tests.
Tennis Australia (TA) said the pair have both been transferred to a quarantine hotel and contract tracing is underway.
Neither player has been publicly identified by TA, but one of the defeated players - Morocco's Elliot Benchetrit - claimed his opponent Denis Kudla was informed of his positive test during the second set, but the pair continued with the American serving out the match.
In a post on his Instagram story, Benchetrit said: "Some very bad news. My opponent has tested positive. At 5-3 (in the second set) they got the result.
"In short: if I had won that game at 5-3 to make it 5-4, I would have qualified for the second round."
As Kudla won the match, both players are out of the tournament and Australian Dane Sweeny goes through to the final round of qualifying.
Argentina's Francisco Cerundolo also posted about a positive Covid test.
He said: "Unfortunately today I tested positive for Covid.
"I am in good health, but I will not be able to continue competing in the tournament."
A spokeswoman for Tennis Australia said: "Local health authorities, the tournament physician and medical team are monitoring each individual. Contact tracing is currently underway to notify close contacts."
All players in Doha were tested upon their arrival into Qatar and were isolated until they returned a negative test, while players who make it to Australia for the grand slam will follow a similar procedure and then follow 14 days of mandatory quarantine.
The tournament will take place in Melbourne between 8 February 21.