Nick Kyrgios has taken yet another swipe at Italy’s Jannik Sinner on the eve of the Australian Open.

The Australian tennis player has been the chief critic of Sinner’s doping case, after a failed test last year saw him banned for one month.

Sinner tested positive to Clostebol, but there was less than one-billionth of a gram found in his samples and a tribunal accepted that he became contaminated through a cream applied by his physio. The world No.1 was given a chance to hit back at Kyrgios at a press conference on Friday but refused to bite.

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Hours earlier, Kyrgios spoke to media at Melbourne Park and was asked about the anxiety around being tested as an elite athlete at random.

“Look, I don’t want to speak too much about it. I think we’ve all been speaking about it. I feel like that’s the only thing tennis has been speaking about the last six months,” Kyrgios said.

“I’ve been tested four times in the last couple months. I got tested in my home three days ago.

“So, for me, it hasn’t been a problem at all in my career.”

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He then took a subtle jab at Sinner, proclaiming that he held no fears about being caught with illegal substances in his system, indicating that he has full trust in his team.

“I’ve been on the tour now for 10-plus years. For me, I’m not worried at all cause I know that I’m really, really on top of what’s going on in my team,” Kyrgios said.

“I’m very confident in myself that I’m not going to be accidentally putting something in my system.”

Sinner, who has grown accustomed to Kyrgios’ barbs, declared he would continue to “block” out criticism ahead of the Australian Open.

“We are at the stage where we don’t know many things,” Sinner said.

“It is what it is. I am here trying to prepare for a grand slam.

“In my mind I know exactly what happened and that’s how I block it. I haven’t done anything wrong – that’s why I’m still here.”

When asked specifically about Kyrgios’ comments, the 23-year-old was quick to shut conversations down.

“I don’t think I have to answer this, to be honest … I don’t want to respond to what Nick says or what any other player says,” Sinner said.