'I haven't done anything wrong'

Sinner unclear about CAS case ahead of Australian Open defence

World number one Jannik Sinner said on Friday he is still in the dark about his hearing at sport's highest court over a doping controversy that continues to weigh on his mind ahead of his Australian Open title defence.

Sinner failed two drug tests in March for low levels of the anabolic androgenic steroid clostebol but was cleared by an independent tribunal in August after it accepted his explanation of unintentional contamination.

However, the World Anti-Doping Agency appealed that decision at the Court of Arbitration for Sport (CAS) in September, leaving the Italian still facing the possibility of being banned for up to two years.

Sinner told reporters at Melbourne Park there was little clarity about the proceedings.

"I know exactly as much as you guys know. We're in a stage where we don't know many, many things," he said.

"Yeah, you think about this, of course. I would lie if I would tell you I forget. No, it's not like this. It's something what I have with me now already for quite a long time.

"But it is what it is. I'm here trying to prepare the Grand Slam. Let's see how it goes."

Sinner did not allow the case to impact his game last season. The 23-year-old enjoyed his best year on the tour and won his second Grand Slam trophy at the US Open.

The handling of the Italian's case, as well as that of Iga Swiatek, by tennis anti-doping authorities attracted strong criticism from some fellow players.

One of the most vocal critics was Nick Kyrgios, who said that it was a "horrible look" for the sport and the Australian has regularly voiced his opinion on Sinner's case via social media.

"I don't think I have to answer this, to be honest," Sinner said. "It's not that you just put it in a (box) and you just say 'I don't think any more about this'.

"In my mind I know exactly what happened. That's how I block it.

"I haven't done anything wrong. That's why I'm still here. That's why I'm still playing. I don't want to respond to what Nick said or what other players say."

Sinner begins his Melbourne Park campaign against Chile's Nicolas Jarry.