Umberto Ferrara, Jannik Sinner's trainer during doping case, says he warned of clostebol risks
Jannik Sinner’s former trainer has said that he was “completely aware” of the risk of contamination from the healing spray at the center of the world No. 1’s positive doping tests and subsequent three-month ban from tennis. Umberto Ferrara, who is now working with Sinner’s compatriot, Matteo Berrettini, said that he has been using Trofodermin […]