ROME (AP) -- Time is running out for appeals to be filed in the case that exonerated freshly-crowned from doping.
The World Anti-Doping Agency (WADA) and Nado Italia, Italy's anti-doping agency, likely have only 1 more day to challenge the (ITIA) on Aug. 20.
There is a 21-day window to appeal that started when the parties received the decision. Any appeal would be filed to the Switzerland-based Court of Arbitration for Sport (CAS).
Sinner tested positive twice for an anabolic steroid in March but was not suspended because the ITIA determined the entered his system unintentionally through a massage from his physiotherapist.
The doping case was kept secret until last month's announcement, and the top-ranked Sinner went on to beat Taylor Fritz in the U.S. Open final on Sunday.
An appeal could jeopardize his U.S. Open title, but Sinner and his legal team have provided detailed scientific evidence to show that his explanation is credible.
Sinner said after winning his second Grand Slam title that the months before his case was resolved were not easy.
"It was very difficult for me to enjoy in certain moments," he said, "so whoever knows me better, they know that something was wrong. But during this tournament, slowly I restarted to feel a little bit more how I am as a person."
While other players have expressed concern with how Sinner's case was kept secret, WADA and Nado Italia would likely be interested only in the scientific details.
An appeal verdict at CAS could come quickly -- even within just a few months -- if the parties agree to cooperate. At least that's how it worked in another high-profile doping case in tennis involving Maria Sharapova.
Sharapova tested positive at the Australian Open in January 2016 for the newly-banned heart medication meldonium. She was banned for 2 years in June that year by the International Tennis Federation.
The Russian star appealed to CAS, had an appeal hearing in New York before three judges that September, and 4 weeks later got the verdict that cut her ban to 15 months.
The entire process for Sharapova with CAS took just 4 months -- far shorter than most doping cases, which typically last about one year. The timeline can stall with the complexities of picking a judging panel, finding a hearing date and parties exchanging documents and evidence from expert witnesses.
During the Indian Wells hard-court event in March, Sinner tested positive for low levels of a metabolite of clostebol, a banned anabolic steroid that can be used for ophthalmological and dermatological use. It's the same drug for which was suspended by Major League Baseball in 2022.
Sinner tested positive again 8 days later in an out-of-competition sample.
He was provisionally suspended twice by the tennis integrity body because of those test results, but he successfully appealed twice to an independent tribunal judge and was allowed to keep competing on tour.
Sinner said his test results happened because his fitness trainer purchased an over-the-counter spray called Trofodermin in Italy that contained clostebol and gave it to Sinner's physiotherapist to treat a cut on the physiotherapist's finger. The physiotherapist then treated Sinner without wearing gloves.
The ITIA said it accepted Sinner's explanation, after 10 interviews with the player and his entourage, and the independent panel agreed at a hearing on Aug. 15.
Sinner later announced that he had fired his two trainers.
While other players wondered whether Sinner was accorded special treatment, most believed he wasn't trying to dope.
"You can understand why people are upset about it. In anti-doping, it sounds so ridiculous," said Travis Tygart, CEO of the U.S. Anti-Doping Agency, which wasn't involved in the case. "But the science is such that, if the facts are actually proven out, it is actually plausible."
If Sinner did lose in an appeal case to CAS, he would likely face a maximum ban of 2 years instead of 4. Four-year bans are usually reserved for athletes unable to show their positive doping test was unintentional.
Sinner provided a clear explanation to an independent tribunal in London, which judges cases brought by the tennis integrity body.
Any possible ban would likely be backdated to March.
Neither WADA nor Nado Italia tend to announce appeals, so it would likely be up to CAS to communicate if there is a case brought before the sports court.
In addition, Giovanni Fontana, an Italian lawyer who has worked on about 100 doping cases over 30 years, recently The Associated Press that Sinner's two trainers could risk a separate inquiry in Italy -- pointing to the 4-year suspension for a club doctor at an Italian soccer team in 2018 for administering Trofodermin to a player.