Joseph Parker is free to box again after UK Anti-Doping concluded that his positive cocaine test was caused by contamination from his own nutritionist.

The former world heavyweight champion from New Zealand tested positive in two separate drug tests around his fight with Fabio Wardley at London's O2 Arena on 25 October 2025. He was tested that same night by the Voluntary Anti-Doping Association (Vada), an independent body that boxers volunteer to be tested by outside of official requirements. He then failed a UK Anti-Doping (Ukad) test in the early hours of 26 October. Wardley won the fight on points.

Parker was charged by Ukad in February 2026. He has always denied knowingly taking any banned substance, and on 6 March 2026 he submitted evidence to Ukad pointing to the nutritionist he had hired for the Wardley bout. The nutritionist told Ukad he was a regular cocaine user and had taken the drug daily in the week leading up to the fight.

Parker's case was that he had been exposed to cocaine through close contact with the nutritionist. Ukad accepted that he had gathered sufficient evidence to prove his adverse finding resulted from that exposure. The anti-doping body described the nutritionist as a "regular user of cocaine." BBC Sport

Parker served a three-month suspension. Ukad cleared him to return to boxing in early August 2026. The Athletic

The case highlights a lesser-known pathway by which a banned substance can enter an athlete's system. Anti-doping rules hold athletes strictly responsible for what turns up in their samples, but regulators can reduce or lift penalties when an athlete proves they bore no fault — for example, by showing contamination from someone in their inner circle.

For Parker, the outcome clears his name and his path back to the ring. The 34-year-old from South Auckland, a former WBO heavyweight champion, can now resume his career after a layoff that spanned the better part of a year. His next opponent has not been announced.