Croatia's Borna Coric has told fans he is feeling well and experiencing no symptoms after contracting the novel coronavirus at Novak Djokovic's controversial Adria Tour tournament.

Djokovic, Coric, Grigor Dimitrov and Viktor Troicki all tested positive for COVID-19 after playing in the event in Serbia and Croatia, which drew big crowds and saw the players pose for pictures together.

World No. 1 Djokovic, who organised the charity event, has come in for heavy criticism after the players were pictured hugging at the net, playing basketball and partying together.

"A few days have passed since I tested positive for Covid-19," world number 33 Coric said on Twitter, with a picture of him standing on a treadmill.

"I'm extremely grateful that I still feel well and don't have any symptoms ... TY very much for all the messages of love and support I have received whilst isolating."

Djokovic has apologised and said the timing of the event was "too soon" while world number three Dominic Thiem, who played in the Belgrade leg, said players behaved "too euphorically".

Djokovic's compatriot, Manchester United midfielder Nemanja Matic, came to his defence, saying there has been a "campaign" against him despite the event breaking no local rules.

In an open letter published by Serbian media, Matic said the "mice" had came out of their holes to criticise Djokovic.

"Very soon the cat will be on the court, and the mice back in the hole," he wrote. "The only thing I hold against Novak is that he apologised to the mice who criticise him for no reason.

"No, Nole. They will apologise to you - soon." (Reporting by Sudipto Ganguly in Mumbai; editing by Peter Rutherford)

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