Australian sprinter Jessica Peris could be banned for up to four years after testing positive to three banned metabolites.
Australian Sports Anti-Doping Authority boss David Sharpe said on Thursday he was confident the correct procedures had been followed when Peris failed a doping test last October.
Peris insisted she was innocent of any wrongdoing, claimed the testing had been botched because a blood sample provided by her on the same day produced a negative result.
She also slammed ASADA for taking three months to inform her of the positive result.
The 27-year-old could be banned from competition for a maximum four years if testing of her B sample also came up positive.
The positive test for three prohibited metabolites triggered a mandatory provisional suspension which ruled Peris out of the recent Commonwealth Games trials on the Gold Coast.
"Due to the nature of the prohibited metabolites detected in the initial urine screen, an additional scientific analysis was required before the positive test could be declared and the athlete notified," ASADA said in a statement.
"As a result of the type of substance detected, the athlete was subject to a mandatory provisional suspension from all competition, in accordance with the World Anti-Doping Code and the Athletics Australia (AA) Anti-Doping Policy.
"This suspension was imposed shortly after Ms Peris was notified of her positive test.
"No prohibited substances were detected in the blood samples.
"Blood and urine screens are used to detect different substances and substances clear from urine and blood at different rates."
Sharpe said he was confident in the testing process and also commended AA for its full co-operation.
"Our testing program is rigorous and professional and is designed to detect doping, with the ultimate aim of protecting the right of clean athletes to fair competition," Sharpe said.
Peris had enjoyed a career-best summer season, lowering her personal bests to 11.41 seconds in the 100m and 23.13 in the 200m - times which would have put her right in contention for a berth in the Australian team for the April 4-15 Commonwealth Games.
"I am looking forward to fighting any doping allegation brought against me by ASADA and ensuring my reputation as a clean athlete continues," she said in a statement.
Peris's mother Nova was the first indigenous Australian athlete to win Olympic gold as a member of the Hockeyroos at the 1996 Atlanta Games.
She switched to track sprinting, winning the 200m gold medal at the 1998 Commonwealth Games in Kuala Lumpur and competing at the 2000 Sydney Olympics.
Australian Associated Press
