Tennis star Nick Kyrgios has slammed German player Alexander Zverev as "selfish" for failing to self-isolate in a series of fiery Instagram videos.
Recent footage emerged of Zverev partying in the wake of the Adria Tour debacle before he apologised for his role in Novak Djokovic's exhibition tournament.
The tournament saw the world No 1, Grigor Dimitrov, Borna Coric and Viktor Troicki plus a number of entourage members, including Djokovic's wife, test positive for Covid-19.
Zverev tested negative but expressed remorse at being involved in the event, which flaunted social distancing with disastrous results.
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"I deeply apologise to anyone that I have potentially put at risk by playing this tour," the 23-year-old said in a statement. "I will proceed to follow the self-isolating guidelines advised by our doctors. As an added precaution my team and I will continue with regular testing."
Kyrgios, however, was unimpressed by Zverev's response, openly slamming him on social media.
"So I wake up and I see more controversial things happening all over the world but one that stuck out for me was seeing Sascha Zverev again, again, again, how selfish can you be?" Kyrgios said in a video posted to his Instagram story. "How selfish can you be? I mean, if you have the audacity to put out a tweet that you made your management write on your behalf saying your going to self-isolate for 14 days and apologising to f*****g general public for putting their health at risk, at least have the audacity to stay inside for 14 days, my god. Have your girlfriend with you for f*****g 14 days. Pissing me off, this tennis world is pissing me off, seriously, how selfish can you all get."
Zverev has also signed up to play in a Berlin tennis tournament in July that will allow crowds of up to 1000 fans in the stands.
There will be two events in the German capital — one outdoors at the Steffi Graf Stadium and one indoors at the city's historic Tempelhof Airport.
Around 4000 spectators watched the Belgrade event of the Adria Tour where there was no social distancing. Players were also photographed shirtless, dancing the night away at a packed Belgrade club.
Kyrgios described the staging of the event as "boneheaded".
But when asked about whether player behaviour could threaten the US Open, tournament director Stacey Allaster said she had "a lot of confidence in these professional athletes".