Novak Djokovic declared that Jannik Sinner’s doping case is damaging tennis – and made the claim just minutes before the Italian’s defeat to Carlos Alcaraz at the China Open. Sinner, who won the US Open last month, twice tested positive for an anabolic steroid in March, but an independent tribunal determined he was not to blame and imposed no punishment.

The tribunal accepted Sinner’s explanation that the banned substance entered his body as a result of a massage from his physio, who had used a spray containing the steroid to treat a cut on their finger. However, the prospect of a suspension has re-emerged since the World Anti-Doping Agency (WADA) launched an appeal against a ruling of “no fault or negligence”.

WADA has lobbied the Court of Arbitration for Sport, seeking to impose a ban of up to two years on the 23-year-old. The appeal was lodged last Thursday but was not announced until Saturday morning, while Sinner was in action at the China Open

The world No.1 reached Wednesday’s final in Beijing, only to see his 15-match winning streak halted by Alcaraz in three thrilling sets. Meanwhile, Djokovic was appearing at a press conference at the Shanghai Masters.

The 24-time grand slam winner criticised the way the Sinner case was being handled, highlighting “way too many inconsistencies” and “way too many governing bodies”.

Pressed on WADA’s recent intervention, Djokovic said: “I think it’s quite obvious that we have a system that is not working well. I guess that’s probably something that even the people who are not following our sport are realising.

“There’s way too many inconsistencies, way too many governing bodies involved. Just this whole case is not helping our sport at all.