The case revolves around French professional tennis player Mathieu Montcourt, who appealed a sanction imposed by the Association of Tennis Professionals (ATP) for violating its Anti-Corruption Program by placing bets on tennis matches. The ATP initially recommended a three-month suspension and a $20,000 fine, but after negotiations, the Anti-Corruption Hearing Officer (AHO) reduced it to an eight-week suspension and a $12,000 fine. Montcourt admitted to placing 36 small bets totaling $192 between June and September 2005, resulting in a net loss of $36.60, but stressed he never bet on his own matches or tournaments he participated in. He claimed ignorance of the rules at the time and ceased betting once he became aware of the prohibition. The AHO acknowledged mitigating factors, such as the small amounts wagered, the lack of influence on match outcomes, and Montcourt’s cooperation, but upheld the sanction, stating that ignorance of the rules was not a valid defense. Montcourt appealed to the Court of Arbitration for Sport (CAS), arguing the penalty was disproportionate and harmed his career, including missing a wild card opportunity for the 2008 US Open. The CAS panel considered the timing and impact of the suspension, recognizing that an eight-week ban during a competitive period could unfairly affect his participation in major events. The case highlights the tension between enforcing anti-corruption rules and ensuring sanctions are proportionate, particularly for minor and unintentional violations. The ATP defended its decision, emphasizing that Montcourt, as a professional player since 2002, had agreed to abide by ATP rules, which prohibited wagering regardless of whether the events were ATP-sanctioned. The panel rejected Montcourt’s argument that online betting was private entertainment, affirming the importance of maintaining public trust in the sport’s integrity. While acknowledging Montcourt’s admission of guilt as a mitigating factor, the panel upheld the sanction as proportionate but adjusted the remaining suspension to five weeks due to procedural delays and unintended consequences, such as the de facto one-week suspension in 2008 that cost him the US Open wild card. The panel deemed this week should carry triple weight due to its collateral effects, which were not Montcourt’s fault. The CAS partially upheld Montcourt’s appeal, reducing the suspension to five weeks effective from July 6, 2009, while confirming the $12,000 fine. The ruling underscores the strict enforcement of anti-corruption measures in professional tennis while recognizing the need for fairness in sanction timing and impact. The decision balances upholding the sport’s integrity with mitigating disproportionate career consequences for the athlete.