Double Olympic gold medallist Diana Taurasi's B-sample has come back positive and she faces a possible two-year ban, which would rule her out of next year's Olympics in London.
The Phoenix Mercury star, who played on the United States teams that won Olympic gold in Athens in 2004 and Beijing 2008, tested positive for the banned stimulant modafinil while playing in Turkey's league for Fenerbahce.
An official at Taurasi's Turkish club, Fenerbahce, also would not confirm the report and said the team had not been notified of the result.
"[We've] seen those reports, but there is no official report," Taurasi's lawyer Howard Jacobs told Associated Press.
"It's disconcerting that it would come out before they finished the process.
"The earliest we would know would be tomorrow."
Taurasi was tested following a league game on November 13 and the positive result was confirmed last month.
Taurasi had been provisionally suspended by Fenerbahce pending the result of her B-sample test, which was analysed at the doping lab at Hacettepe University in Ankara.
Modafinil is used to counter excessive sleepiness due to narcolepsy, shift-work sleep disorder or sleep apnea, according to drug manufacturers.
But the drug has been involved in several doping-related controversies.
American sprinter Kelli White, who won the 100 and 200 metres at the 2003 World Championships in Paris, had both of her medals stripped after testing positive for the substance.
Modanafil was also one of the cocktail of drugs that banned British sprinter Dwain Chambers admitted to taking.
Taurasi led the WNBA in scoring for a league-record fourth straight year, averaging 22.6 points.
Taurasi is one of many American stars who play overseas in the winter because salaries are significantly higher than the WNBA's summer league.
If the positive B-sample finding is confirmed by Turkey's basketball federation, it could lead to a ban of up to two years for Taurasi.
Meanwhile, two of Taurasi's teammates at Fenerbahce resisted doping tests in Turkey because they do not trust the lab that tested her samples, Turkey's Haberturk newspaper said.
Penny Taylor of Australia and Hana Horakova of the Czech Republic provided samples only after the Turkish federation agreed to send them to Germany for testing at a lab in Cologne.
The two players were tested after Fenerbahce's Turkish league game against Besiktas on Sunday (January 1).
A Fenerbahce official confirmed the report.