ANTI-DOPING: CAS CASE NOTE
By Kim Gamboni, Attorney, VALLONI Attorneys-at-Law, Zurich, Switzerland
Facts of the Case
In an award, handed down on 27 November 2025, the Court of Arbitration for Sport (CAS) in the case of World Anti-Doping Agency (WADA) v. Finnish Center for Integrity in Sports (FINCIS) & Miro Sihvonen (CAS 2025/A/11339) reviewed a sanction imposed upon a Finnish professional motocross rider, following an adverse analytical finding from a sample collected on 14 July 2024. The sample contained anabolic agent findings including a drostanolone metabolite and 19-norandrosterone (nandrolone).
The rider accepted the anti-doping rule violation (ADRV) but disputed intent and argued that the presence of the prohibited substances was connected to an injection administered in Brazil shortly before a race, in a context described as hectic and pain driven.
In first-instance proceedings, the Anti-Doping Disciplinary Board of FINCIS imposed an 18-month ban, which the World Anti-Doping Agency (WADA) appealed to CAS.
The appeal focused on the applicable period of ineligibility under the Finnish Anti-Doping Rules (FADR), which came into force on 1 January 2021, apply to all organised sport in Finland and are aligned with the WADA Code; in particular, the athlete’s burden to establish that the violation was not intentional.
Under Article 10.2.3 of the FADR, the burden of proving lack of intent lies on the athlete, who must show that the ADRV was neither deliberate nor reckless. The applicable standard of proof is the balance of probabilities (that is, more likely than not).
Under Article 10.2.1.1 of the FADR, the default sanction is four years, unless the athlete establishes that the violation was not intentional.
Decision
CAS accepted that the athlete had produced sufficient factual evidence to establish the injection as the source of nandrolone. However, CAS rejected the argument that drostanolone resulted from contamination of the nandrolone product, holding that the athlete had not demonstrated, on a balance of probabilities, that contamination was the most likely explanation, as opposed to a mere scientific possibility.
As a result, CAS concluded that the violation, with respect to drostanolone, must be treated as intentional, within the meaning of the FADR, triggering the standard four-year period of ineligibility. CAS, therefore, set aside the FINCI decision and imposed a four-year period of ineligibility, starting on the date of the award, with credit for any period of provisional suspension effectively served, and disqualified the athlete’s competitive results from 14 July 2024 to 16 August 2024.
Comments
This award is a clear reminder that “possible contamination” is not enough: an athlete must show that the proposed source mechanism is more likely than not in the particular circumstances.
Where multiple prohibited substances are detected, establishing a credible source pathway for only one substance may be insufficient to rebut intentionality for the outcome of the case. Even where a credible non-performance narrative exists, for example, treatment administered shortly before competition by support personnel, CAS will typically expect athletes to build an evidence-based pathway for each relevant substance if they seek to avoid the default four-year sanction.
In practical terms, the case underscores compliance lessons for athletes and entourages competing internationally: medical treatments given “in the heat of the moment” (especially in jurisdictions with different medication practices) create predictable anti-doping exposure, unless there is strict documentation, verification of substances, and a careful chain-of-custody around any administered product.
For counsel, the decision also shows how CAS distinguishes between (i) proving a credible source for one substance; and (ii) failing to prove an asserted contamination theory for another—where the latter can be decisive for intent classification and, therefore, sanction length.
This is particularly relevant where an athlete’s account rises above speculation for one marker (here, nandrolone) but remains evidentially insufficient for another (here, drostanolone).
Kim Gamboni can be contacted by e-mail at gamboni@valloni.ch