Outspoken Australian Nick Kyrgios questioned Dominic Thiem's intellect on Wednesday after the World No. 3 told him to stop criticising fellow tennis stars Alexander Zverev and Novak Djokovic for taking risks with COVID-19. Kyrgios said Thiem wasn't on the same intellectual level after the Austrian called his criticism cheap and claimed it was bad luck that Zverev was caught partying after promising to self-isolate.

Djokovic, Grigor Dimitrov, Borna Coric and Viktor Troicki all tested positive for COVID-19 after last month's Adria Tour, an exhibition series. "Kyrgios has really done a lot of nonsense himself. That's why I understand even less when he interferes everywhere," said Thiem. "It would be better for him to come clean instead of always criticising others."