Viktor Troicki has tested positive for coronavirus after taking part in an exhibition series organised by Novak Djokovic in Serbia and Croatia.
The top-ranked Djokovic was the face behind the Adria Tour, a series of exhibition events that started in the Serbian capital and then moved to Zadar, Croatia, last weekend.
He left Croatia after the final was cancelled and was tested in Belgrade. Those results are expected later on Tuesday.
Grigor Dimitrov tested positive for the virus, while Borna Coric - who played the Bulgarian on Saturday in Zadar - later confirmed that he had also tested positive.
Troicki played in the first leg staged at Djokovic's tennis complex in central Belgrade from June 13-14, before Dimitrov and Coric tested positive at the second leg in Zadar held from June 20-21.
Troicki, 34, entered Janko Tipsarevic's Eastern European Championship tournament which started in Belgrade last Monday and pulled out after learning that he and his wife tested positive.
"My wife took the test on Friday and I took it on Sunday after she tested positive," Troicki told Serbia's Telegraf website. "Our daughter tested negative."
Djokovic's fitness coach Marco Panichi also tested positive, Serbian daily Sportski Zurnal reported, quoting Croatia's health institute.
Alexander Zverev, Marin Cilic and Andrey Rublev - who all played at the Adria Tour - said they tested negative for the virus but will follow self-isolation guidelines.
The tournament witnessed packed stands during the opening leg in Belgrade, players hugging at the net, playing basketball, posing for pictures and attending press conferences together. Djokovic organised nights out in Belgrade for the players and pictures and videos of him dancing with the other participants at his event were posted on social media.
While the players did not break any Serbian or Croatian government protocols, as neither country required the athletes to maintain any social distancing, the fact that three players and some support staff caught the virus highlights the risks of athletes from different countries being in close proximity to each other.
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