Last year, Sinner tested positive twice for a trace amount of an anabolic steroid in March; the case wasn't made public until August, shortly before the U.S. Open, which he ended up winning for the second of his four Grand Slam titles.
He initially was completely cleared, based on the defense that he accidentally was exposed to the banned substance, Clostebol, via a massage from his then-physiotherapist, Giacomo Naldi. Sinner said his fitness trainer at the time, Ferrara, purchased a product in Italy and gave it to Naldi for a cut on Naldi's finger. Naldi then treated Sinner while not wearing gloves.
Sinner then fired Naldi and Ferrara, and Ferrara was hired briefly by Matteo Berrettini, another Italian player.
>>> Jannik Sinner's doping case: A complete timeline of how it unfolded, on and off the court
The World Anti-Doping Agency appealed the exoneration, and Sinner agreed to serve a three-month ban that ended right before the Italian Open in May of this year.
Sinner, who won Wimbledon this month, will return to action at the Cincinnati Open next month as he prepares to defend his U.S. Open title.
