Diana Taurasi's Turkish club demanded an apology Friday and the resignation of the directors of the doping lab that issued an apparent "false positive" report on the American basketball player.
Fenerbahce also said it would take legal action.
Sekip Mosturoglu, a member of Fenerbahce's executive board, accused the Ankara-based lab of "inadequacies" and said its report declaring Taurasi's "A'' and "B'' samples positive for the banned stimulant modafinil had sullied both the reputation of both the WNBA star and Fenerbahce.
"This is the greatest scandal in world sports," Mosturoglu said. "They cannot get away with simple apologies."
Fenerbahce terminated Taurasi's contract after she tested positive following a Nov. 13 league game. The Turkish Basketball Federation subsequently suspended her from play but lifted the suspension Wednesday.
Mosturoglu said Taurasi's absence had put Fenerbahce's chances to win the Euroleague at "risk."
He also faulted some Turkish Basketball Federation officials for refusing to allow Taurasi's "B'' sample to be tested at another lab and demanded their resignations, too.
"Our club will take every kind of legal action to the compensation of our losses," Mosturoglu said.
Taurasi insisted all along that she never used performance-enhancing drugs. The 28-year-old American will be able to compete at the 2012 Olympics now that she has been cleared of the doping charges.
Modafinil is used to counter excessive sleepiness due to narcolepsy, shift-work sleep disorder or sleep apnea, according to drug manufacturers.
Mosturoglu said Fenerbahce would work hard to convince Taurasi and teammate Penny Taylor to return. Taylor left Fenerbahce in a show of solidarity with Taurasi.
But Taurasi, who plans to return to the WNBA when the season begins in June, told The Associated Press on Wednesday that her return to the Turkish league was "pretty unlikely."
Nevertheless, thousands of Turkish fans urged the star to come back, posting messages on the specially-created comebackdiana.com website.
The World Anti-Doping Agency, which can suspend or revoke the accreditation for doping labs, said it has asked the lab to explain why it declared Taurasi positive for modafinil. WADA, which has 35 accredited labs worldwide, previously suspended the Ankara facility for three months in 2009 for failing to meet international standards.
Mosturoglu said the lab had accepted its mistake only after an international drug-testing expert looking into the Taurasi case pointed out the lab's error.
The federation this week also lifted the provisional suspension for American player Monique Coker, who plays for Ceyhan Belediyesi and had tested positive for modafinil in tests carried out at the same lab.
Associated Press Writer Selcan Hacaoglu contributed to this report.