Reigning US 1500m champion, Regina Jacobs, has been suspended for four years, the United States Anti-Doping Agency (USADA) has announced.
Jacobs had a late-career performance surge
Jacobs tested positive for the banned steroid THG in the summer of 2003.
The 40-year-old veteran abruptly announced her retirement at the US Olympic trials on the eve of the 1500m semi-finals.
Jacobs must now forfeit all results and winnings, including the first-place 1500m finish that brought a US title.
"Clean athletes should be motivated by knowing that Olympic sport has committed its resources and expertise to leveling the playing field by eliminating drugs, including undetectable substances from competition," USADA chief executive Terry Madden
THG is at the centre of the Balco doping scandal that has rocked US Olympic preparations.
Jacobs was one of six US athletes entered in the trials facing doping charges.
World 100m record holder Tim Montgomery failed to
finish in the top three, thereby missing selection.
Olympic 400m silver medallist Alvin Harrison failed to
make the final and his twin Calvin finished fifth.
Former world indoor 200m champion Michelle Collins
withdrew from the trials.
Olympic 4x100m relay gold medallist in 1996, Chryste Gaines failed to qualify for the 100 and later withdrew from the 200.
The eliminations and withdrawals helped ease an awkward problem for US officials, who have vowed to send a clean team to Athens but were facing the possibility of selecting athletes who were still facing doping charges.