The two players had taken part in the exhibition tournament in Belgrade alongside World No.1 Novak Djokovic, World No.3 Dominic Thiem and World No.7 Alexander Zverev among others.
Kyrgios took to social media to blast the decision to host the tournament amid these uncertain times and wrote on Twitter: "Boneheaded decision to go ahead with the 'exhibition' speedy recovery fellas, but that's what happens when you disregard all protocols. This IS NOT A JOKE."
The next leg of the tournament, which was scheduled to be held in Zadar (Croatia) where Djokovic was set to feature in the final against Andrey Rublev, has been cancelled in the wake of players testing positive.
"Hi everyone, I wanted to inform you all that I tested positive for COVID-19. I want to make sure anyone who has been in contact with me during the last few days gets tested!" Coric said in a statement on his official Twitter handle.
"I am really sorry for any harm I might have caused. I am feeling well and don't have any symptoms. Please stay safe and healthy. Lot of love to all!" he added.
Earlier on Sunday, Dimitrov took to social media to reveal that he had tested positive for the deadly virus.
"Hi everyone-I want to reach out and let my fans and friends know that I tested positive back in Monaco for COVID-19. I want to make sure anyone who has been in contact with me during these past days gets tested and takes the necessary precautions.
"I am so sorry for any harm I might have caused. I am back home now and recovering. Thanks for your support and please stay safe and healthy," Dimitrov said on Instagram."