Nick Kyrgios says the high-profile doping cases involving Grand Slam winners Jannik Sinner and Iga Swiatek are "disgusting" for tennis.

Italian men's world number one Sinner still faces the threat of a possible suspension after he twice tested positive for an anabolic steroid in March.

Swiatek, also 23, served a one-month suspension after testing positive for a banned heart medication in August, when the Pole was women's world number one.

"I just think that it's been handled horrifically in our sport," said Australian Kyrgios, 29.

"Two world number ones both getting done for doping is disgusting for our sport.

"It's a horrible look."

Kyrgios is preparing to make his return to competitive action at the Brisbane International, following an 18-month injury-enforced absence since contesting the Stuttgart Open in June 2023.

In that time, the sport's leading players in both the men's and women's games have become involved in controversy over respective failed tests.

While the International Tennis Integrity Agency (ITIA) cleared Sinner of wrongdoing after he twice tested positive for clostebol, the case was taken to the Court of Arbitration for Sport (Cas) after the World Anti-Doping Agency (Wada) launched an appeal.

Swiatek accepted a one-month ban, which ended on 4 December, after the ITIA accepted her positive test for trimetazidine (TMZ) was caused by contamination of the regulated non-prescription medication melatonin.

The treatment of those two players has led to accusations of double standards, with two-time Grand Slam champion Simona Halep saying there were "completely different approaches" to those cases compared to her own.

However the ITIA strongly denies handling these cases any differently.

Kyrgios said: "The tennis integrity right now, and everyone knows it but no one wants to speak about it, is awful.

"It's not okay. I know that people don't like when I just speak out about things, be honest about things."

In addition to making his singles return against Frenchman Giovanni Mpetshi Perricard, Kyrgios is set to partner Novak Djokovic - chasing his 100th Tour-level title in Brisbane - in the men's doubles competition.