Novak Djokovic tested positive for the coronavirus on Tuesday after taking part in a tennis exhibition series he organized in Serbia and Croatia.

The top-ranked Serb is the fourth player to test positive for the virus after first playing in Belgrade and then again last weekend in Zadar, Croatia. His wife also tested positive.

“The moment we arrived in Belgrade we went to be tested. My result is positive, just as Jelena’s, while the results of our children are negative," Djokovic said in a statement.

Djokovic has been criticized for organizing the tournament and bringing in players from other countries amid the coronavirus pandemic.

Viktor Troicki said Tuesday that he and his pregnant wife have both been diagnosed with the virus, while Grigor Dimitrov, a three-time Grand Slam semifinalist from Bulgaria, said Sunday he tested positive. Borna Coric played Dimitrov on Saturday in Zadar and said Monday he has also tested positive.

There were no social distancing measures observed at the matches in either country and Djokovic and other players were seen hugging each other and partying in night clubs and restaurants after the matches.

He left Croatia after the final was cancelled and was tested in Belgrade. The statement said Djokovic was showing no symptoms.

Despite the positive test, Djokovic defended the exhibition series.

Djokovic said he will remain in self-isolation for 14 days and also apologized to anyone who became infected as a result of the series.

Organizers of the Adria Tour said the third stage of the event, scheduled to held next week in Bosnia, has been cancelled.