The theory is someone using the banned substance was giving him a lot of massages, thereby passing on the banned substance "transdermally."
An independent panel held a hearing on Aug. 15 and "determined a finding of No Fault or Negligence applied in the case, resulting in no period of ineligibility," according to the ITIA.
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He will, however, lose the $325,000 and 400 points that he had earned at the tournament in Indian Wells.
FWIW, a substack article from May:
Over the past decade the drug has resurfaced in Italian football and across Italy’s wider sporting landscape. Between 2019 and 2023, 38 Italian athletes have tested positive for clostebol despite the fact it is scarcely produced in oral or injectable form by pharmaceutical companies
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If an athlete handles the cream, even in applying it to another individual, then they can risk testing positive. This has been one of the common defences used in Clostebol cases.
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It remains bewildering, however, that Italy’s athletes are missing the warning sign printed on clostebol creams and sprays in Italy, which clearly states that the product contains ‘doping’ substances.