Erriyon Knighton handed four-year doping ban, likely ruling him out of LA 2028

Erriyon Knighton, a leading U.S. 200-meter sprinter, was given a four-year ban by the Court of Arbitration for Sport on Sept. 12, 2025, a sanction that all but eliminates the prospect of his competing at the 2028 Olympic Games in Los Angeles.

CAS upheld appeals by the World Anti-Doping Agency and track-and-field investigators after an out-of-competition sample collected in May 2024 tested positive for trenbolone, a prohibited anabolic steroid commonly associated with livestock farming. The panel reduced the period of ineligibility to account for more than two months Knighton served under a provisional suspension last year; the ban begins Sept. 12, 2025, and is scheduled to expire in early July 2029.

Knighton, who won the world silver medal in the 200 meters in 2023 and is a two-time Olympic finalist, was previously cleared to compete after an independent arbitration tribunal accepted his explanation that the positive test resulted from food contamination. That ruling, which found he bore no fault or negligence, allowed him to run at the U.S. Olympic trials and at the Paris Games in 2024.

CAS, however, said the evidence presented by Knighton and his team fell short of proving the source of the adverse analytical finding. The athlete had argued the ingestion of an oxtail dish purchased in central Florida had been contaminated with trenbolone. The CAS panel said there was "no proof that would support the conclusion that oxtail imported into the USA would be likely to contain trenbolone residues at the level required to have caused the athlete's Adverse Analytical Finding." WADA and the athletics investigators had described the contamination scenario as statistically implausible.

The CAS ruling does not strip Knighton of his fourth-place finish in the Paris 200m; the panel declined to disqualify that result. It did, however, disqualify certain earlier results retroactively for a limited window: performances from March 26 through April 12, 2024, were nullified.

Knighton, who was born in Georgia, did not qualify in the 200m for Team USA at the world championships opening in Tokyo this week. His career includes world championship silver and bronze medals in the 200 meters from the past two global championships.

USADA initially pursued sanctions after the May 2024 test but did not impose a ban following the arbitration decision that found no fault or negligence. WADA and athletics investigators then appealed that outcome to CAS, seeking a maximum four-year suspension and broader disqualification of results. CAS granted the full length of the ban sought but only partially granted the request to annul Knighton's results.

The decision removes one of the sport's young sprint talents from international competition for most of the remainder of the decade and alters the composition of contenders in future global events, including the 2029 world championships and the 2028 Olympic program in Los Angeles. Knighton and his representatives have the option to release further statements or to pursue other legal avenues, but the CAS award is the latest and most authoritative ruling in the matter to date.