Óscar Zambrano Preciado v. Confederación Sudamericana de Fútbol (CONMEBOL)

At a glance

Parties

Óscar Zambrano Preciado (Ecuadorian professional footballer, then with Liga Deportiva Universitaria, Quito) v. Confederación Sudamericana de Fútbol (CONMEBOL)

Case no.

CAS 2024/A/11036

Forum and rules

Court of Arbitration for Sport, appeal procedure under the Code of Sports-related Arbitration (expedited). Applicable rules: CONMEBOL Anti-Doping Regulations (2021 edition) and CONMEBOL Disciplinary Code, with Paraguayan law subsidiarily.

Tribunal

Jaime Castillo (President), Gustavo Albano Abreu, Alexander McLin

Sector

Football; anti-doping (chlorthalidone)

Outcome

Appeal partially upheld (operative part 31 March 2025; reasoned award 7 November 2025): the period of ineligibility was reduced from 16 to 12 months, running from the date of the CONMEBOL decision. All other requests were rejected.

The dispute

The player tested positive for chlorthalidone, a diuretic and masking agent on the WADA 2024 Prohibited List, in an out-of-competition test on 19 February 2024 and in a test after the CONMEBOL Recopa 2024 first-leg match between LDU and Fluminense on 22 February 2024. He showed that on 4 February 2024 he had taken one 50 mg chlorthalidone tablet. A pharmacy employee had recommended it after he suffered an allergic reaction to food contaminated with shrimp. The CONMEBOL Disciplinary Commission found the violation unintentional and committed with no significant fault or negligence, but rated his fault as "normal" and imposed 16 months' ineligibility from notification of its decision. On appeal, the player sought a finding of "light" fault, or at least the 12-month minimum, and asked for the sanction to be backdated or reduced for procedural delays and for his exclusion from the Copa Libertadores 2024. CONMEBOL argued that he took none of the basic precautions, had attended two CONMEBOL anti-doping courses, and was never provisionally suspended.

Key holdings

1. Since the 2015 WADA Code reform, CAS case law adapts the Cilic categories to two degrees of fault: normal (12–24 months) and light (0–12 months). The objective criteria decide the category; the subjective criteria place the athlete within it. ¶¶ 81–87
2. The player's fault was normal. His symptoms worsened only after he took the tablet. He was not at a level of distress that prevented him from checking the packaging, researching the substance or consulting his club doctor, whom he later called without difficulty. A professional athlete must meet a standard of care far above that of an ordinary person. ¶¶ 94–100, 104
3. Subjective criteria can move an athlete into a different category only exceptionally. Here they could not outweigh the almost complete absence of diligence. ¶¶ 102–103
4. Several subjective factors place the fault at the lowest end of the normal category: the player's youth (19 years), inexperience and limited formal education; the authority he gave to the pharmacy employee; his only introductory anti-doping education from two CONMEBOL sessions; the absence of any intent to enhance performance or mask; and, above all, the high stress caused by the allergic reaction. The Panel imposed 12 months' ineligibility. ¶¶ 107–124
5. Under Article 29 of the Anti-Doping Regulations, the ineligibility runs from the date of the appealed decision, without deductions. The player was never provisionally suspended and kept playing for LDU and then Hull City. LDU's decision not to register him for the Copa Libertadores 2024 group stage is res inter alios acta for CONMEBOL. ¶¶ 126–133
6. Procedural requests rejected. CONMEBOL's request to exclude Dr Terán's written expert evidence failed because that evidence was immaterial to the outcome. Its request for the player's employment contract with LDU failed because that contract was irrelevant to the anti-doping violation. ¶¶ 52–56
7. The cost rulings in operative points 3 and 4 are redacted in the published award. Operative part

Procedural history

1. 19 and 22 February 2024Out-of-competition test in Quito, then a post-match test after the CONMEBOL Recopa 2024 first leg. Both samples were later found positive for chlorthalidone.
2. 5 and 7 March 2024The Cologne laboratory reported the adverse analytical findings for the two A samples.
3. 16 August 2024The CONMEBOL Disciplinary Unit charged the player under Articles 6 and 7 of the Anti-Doping Regulations and offered a case resolution agreement with two years' ineligibility.
4. 4 November 2024The CONMEBOL Disciplinary Commission imposed 16 months' ineligibility from notification. Its reasons were notified on 13 November 2024.
5. 25 November 2024Statement of appeal filed with CAS, with a request for provisional measures. The request was withdrawn on 3 December 2024 once the parties agreed an expedited procedure.
6. 16 January 2025Panel constituted.
7. 13 March 2025Hearing by videoconference.
8. 31 March 2025Operative part of the award: appeal partially upheld and ineligibility reduced to 12 months.
9. 7 November 2025Reasoned award issued.

Tribunal, counsel and experts

Decided by

• Jaime Castillo President, Court of Arbitration for Sport Panel — appointed by the institution
• Gustavo Albano Abreu Co-arbitrator, Court of Arbitration for Sport Panel — appointed by the claimant
• Alexander McLin Co-arbitrator, Court of Arbitration for Sport Panel — appointed by the respondent

Experts

Enrique Terán (claimant) · Luis Ferrari (claimant)

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Keywords

• anti-doping
• chlorthalidone
• diuretics and masking agents
• specified substance
• no significant fault or negligence
• degree of fault
• Cilic criteria
• objective and subjective criteria
• period of ineligibility
• start of ineligibility
• provisional suspension
• anti-doping education
• allergic reaction
• pharmacy recommendation
• CONMEBOL Recopa 2024
• Copa Libertadores 2024
• LDU Quito
• CONMEBOL Anti-Doping Regulations

Summary generated with AI from the published documents — refer to the award for the authoritative text.