Calvin Harrison, a member of the United States' 2000 Olympic Games gold medal-winning 400metres relay team and a potential member on this year's squad, has been suspended for two years for a second doping violation.
According to a release from the US Anti-Doping Agency, Harrison tested positive for the prohibited stimulant modafinil at the 2003 USA Outdoor Track and Field Championships in Stanford, California on June 21st, 2003.
The 30-year-old begins his suspension from all sanctioned competition immediately, after an arbitration panel rejected his appeal on July 26th. Harrison's first offence also involved a prohibited stimulant and occurred at the 1993 US Junior National Championships.
As a two-time offender he was hit with the two-year suspension.
In addition to being ruled ineligible for the Athens Olympics, he forfeits all winnings from the date of the positive test. That includes a second-place finish in the 400m at the Stanford event and the United States' gold medal-winning relay performance at the World Championships in August 2003.
Modafinil is a central nervous system stimulant that was prohibited at the time of the test because it is related to the classes of substances banned under IAAF rules.
Harrison, a North Carolina resident, ran the third leg on the 2000 Olympic team and the first leg at the 2003 World Championships.
He was to be a member of the relay pool for this year's Olympic squad after finishing fifth in the 400m at the Olympic trials.