Jannik Sinner has revealed he’s had “sleepless nights” amid his ongoing anti-doping controversy. The World No 1 said that he is “very disappointed and also surprised” after the World Anti-Doping Agency (Wada) announced that it would be appealing the decision to clear the Italian of a doping offence.

Djokovic sympathised with the Italian and touched upon the inconsistencies in dope testing and the non-functionality of the system.

The men's world No. 1 could face a two-year ban. Here's what to know about the doping proceedings against him so far

The appeal to the Switzerland-based Court of Arbitration for Sport (CAS) means that the case might not be resolved before Jannik Sinner begins defense of his Australian Open title in January.

World number one Jannik Sinner said on Monday that he was in "a very difficult moment" and enduring sleepless nights over his doping case.

The world No. 1's doping case continues, even though WADA is not attempting to prove he intentionally took clostebol.

Martina Navratilova, 18-time Grand Slam champion, criticized WADA for appealing Jannik Sinner’s doping case verdict. Martina Navratilova, former world No 1 and 18-time Grand Slam champion, has strongly criticized the World Anti Doping Agency (WADA) after their decision to appeal Jannik Sinner’s innocence verdict over doping case.

World No. 1 Daniil Medvedev has shared his thoughts on the Jannik Sinner doping controversy, which has been brought back into the spotlight after WADA appealed his clearance.