Adria Tour director Djordje Djokovic, brother of world No1 Novak - who organised the ill-fated event, has admitted the multiple Covid-19 positive results by its participants is worst imaginable outcome.
Bulgarian Grigor Dimitrov pulled out of the tournament in Croatia's coastal resort of Zadar after feeling unwell following his match with Coric on Saturday.
He informed the organisers ahead of Sunday's final he had tested positive upon his return to his Monte Carlo residence, leading to the cancellation of the showdown between Novak and Russian Andrey Rublev.
Croatian Borna Coric tested positive on Monday as did Serb Viktor Troicki, who did not take part in the Zadar leg of the Adria Tour but featured in the first leg staged at Novak's tennis centre in Belgrade on June 13 and 14.
Novak's fitness coach Marco Panichi and Dimitrov's coach Christian Groh also tested positive.
"This was the worst possible scenario," event director Djordje told Serbia's Prva Television.
"Novak was not obliged to take the test in Croatia as he had no symptoms. He took the test straight after his flight landed in Belgrade.
"Around 100 people were tested and I was hard-hit by news that some of them came back positive, especially my childhood friend Borna Coric. We wish all of them a speedy and painless recovery."
Djordje said he had made the decision to cancel the Zadar final in order to contain the damage.
"We wanted to protect every player and fan after learning that Dimitrov tested positive. It was a charity event and all we wanted was to play tennis and give the fans a good show," he said.
A sellout 4,000 crowd attended both days of the Belgrade event and as many turned up to watch the Zadar event, with its Visnjik tennis complex half-full after Croatia's authorities ordered spectators to implement social distancing.
The third leg which was due in Montenegro on June 27 and 28 was scrapped during the Belgrade event amid coronavirus concerns voiced by the Montenegrin government.
The final leg scheduled for Bosnia's city Banja Luka on July 3 and 4 is likely to be cancelled, although the tour's organisers are yet to confirm its fate.
However, Australian player Nick Kyrgios had described the decision to go ahead with the exhibition matches as “bone headed” in a Twitter post.
“Speedy recovery fellas, but that’s what happens when you disregard all protocols. This IS NOT A JOKE.”
British men's No1 Dan Evans told the BBC that staging the event was a "poor example to set."
“Put it this way, I don’t think you should be having a players’ party and then dancing all over each other,” Evans said. “He should feel some responsibility in his event and how it’s transpired.”