Former American sprinter Jon Drummond has been given an eight-year ban by the United States Anti-Doping Agency (USADA) for violating its anti-doping rules.
Drummond, who was in the USA's team which won gold in the 4x100m relay at the 2000 Olympics, was found guilty of possessing, trafficking, and administering banned performance-enhancing substances to an athlete by an independent North American Court of Arbitration for Sport panel.
The 46-year-old was coaching Tyson Gay when the sprinter was suspended in June 2013 after testing positive for a banned anabolic steroid in two out-of-competition tests.
A statement from USADA chief executive Travis Tygart read: "Coaches have an inherent responsibility to protect athletes - not take advantage of them - but to ensure that they receive the support, training and advice they need to win fairly and in accordance with the rules."
The ban prevents Drummond from coaching, training or advising athletes and participating or coaching at any event sanctioned by USA Track & Field, the International Association of Athletics Federations or any other WADA Code signatory.