Lleyton Hewitt’s 16-year-old son Cruz practised with world No 1 and defending Australian Open champion Jannik Sinner at Melbourne Park and it didn’t take long for Nick Kyrgios to post a negative response.

Hewitt is a rising star of Australian tennis and has been granted a wildcard into the qualifying event for the first Grand Slam of 2025, so the chance to practice with Sinner ahead of what he hopes could be his debut in a main draw of a major tournament was too good to ignore.

Yet any positive story around Sinner tends to draw a quick response from Kyrgios, who has been the most outspoken critic of the world No 1 since he failed two drug tests last March.

Kyrgios described Sinner positive doping tests as “disgusting” as he spoke to the media ahead of his return to action after a long injury lay-off.

The combative Australian has been a vociferous critic of Sinner since he escaped a ban following a positive doping test after an anabolic steroid was found to be in his system.

The World Anti-Doping Agency has appealed a decision by the International Tennis Integrity Agency to clear Sinner of blame and Kygios piled the pressure on the defending Australian Open champion as he spoke to the media in Brisbane.

“I have to be outspoken about it because I don’t think there are enough people that are speaking about it. I think people are trying to sweep it under the rug.

“I just think that it’s been handled horrifically in our sport. Two world No 1’s both getting done for doping is disgusting for our sport. It’s a horrible look.

“The tennis integrity right now – and everyone knows it, but no one wants to speak about it – it’s awful. It’s actually awful. And it’s not OK.

“I know that people don’t like when I just speak out about things, be honest about things.”

His comments last week were the latest attack from Kyrgios on Sinner, but some Instagram users suggested he may have gone too far with his comments criticising teenager Hewitt for accepting a chance to share a court with the Italian.

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“Love ya Cruz but this is wild,” wrote Kyrgios, with a tearful emoji signing off his message.

Kyrgios added additional messages that included needle and broken heart emojis.

His comments sparked some replies claiming Kyrgios had overstepped the mark by lashing out at a teenager, with Cruz’s post also featuring an earlier image of him with Sinner when he was a lot younger.

Cruz’s Dad Lleyton is unlikely to have been impressed by Kyrgios sniping at his son and the duo may be set for an interesting conversation if they bump into each other at Melbourne Park ahead of the Australian Open.

Yet Kyrgios appears to be intent on continuing to attack Sinner, as he had made it clear he hopes to be drawn against the Italian in the opening Grand Slam of the year.

“Let’s be honest, I just want to go out there and I really want to play Sinner,” Kyrgios said on the Nothing Major podcast.

“If I played him in the Australian Open, I’d get every person in the crowd to get on him. I would turn it into an absolute riot. All respect would go out the window and I would just do anything to win.”

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