Collins gets 8-year ban

The 33-year-old Collins is the first athlete in the BALCO case to be suspended without a positive doping test or an admission of drug use.

A hearing panel of the American Arbitration Association (AAA)/North American Court of Arbitration for Sport (CAS) found that "USADA has proved, beyond a reasonable doubt, that Collins took EPO (erythropoietin), the testosterone/epitestosterone cream, and THG (tetrahydrogestrinone)."

It added in a statement released from its Colorado Springs, Colorado, headquarters, that Collins had "used these substances to enhance her performance and elude the drug testing that was available at the time".

USADA said the panel found that Collins' "participation in the BALCO conspiracy amounted to a cover up and because her doping took place over an extended period it is appropriate to double the four years received by other BALCO athletes and to suspend her for eight years".

The Bay Area Laboratory Co-operative (BALCO) scandal erupted last year after Trevor Graham, ex-coach of world 100 metres record holder Tim Montgomery and Marion Jones, sent a syringe containing the previously undetectable designer steroid THG to the U.S. Anti-Doping Agency.

BALCO laboratory head Victor Conte is facing charges of distributing illegal performance-enhancing drugs to top sportsmen and women.

USADA chief executive officer Terry Madden said: "The CAS panel's decision confirms that those who violate the rules will be sanctioned as part of USADA's ongoing efforts to protect the rights of the overwhelming majority of U.S. athletes that compete drug-free."

To date, 13 athletes have received sanctions for violations involving drugs associated with the BALCO doping conspiracy, USADA said.

Montgomery is facing doping charges while Conte has alleged that he supplied drugs to multiple Olympic champion Jones. She denies using drugs and has never failed a dope test.