Wimbledon champion Sinner was initially cleared by an independent tribunal of any wrongdoing last August but the World Anti-Doping Agency (Wada) appealed against the panel’s ruling that he “bore no fault or negligence”.
The 23-year-old ultimately accepted a three-month ban in February after reaching a settlement with Wada.
Wada said it accepted the four-time Grand Slam champion did not intend to cheat, but he bore responsibility for “the entourage’s negligence”.
Sinner said the substance clostebol, which can increase muscle mass, entered his system when Naldi applied an over-the-counter spray to treat a cut on his hand.
Ferrara said he provided the spray to Naldi for personal use and warned him not to use it on Sinner.
After the departures of Ferrara and Naldi, Sinner appointed fitness coach Marco Panichi and physiotherapist Ulises Badio in September 2024.
However, he parted ways with the pair shortly before this year’s Wimbledon.
Sinner made his return to tennis at the Italian Open in May.
He lost the French Open final to Carlos Alcaraz in a five-set thriller in June, before beating the Spaniard in the Wimbledon final earlier this month to win his fourth Grand Slam.
