Richard Virenque, the four-time Tour de France King of the Mountains winner, took up to 100 injections of the banned drug EPO every year, according to Willy Voet, Festina's sacked masseur.
Virenque (28), has persistently denied ever taking banned substances, declaring on Tuesday that official tests that appeared to contradict him were false.
But Voet, in an interview published in today's France Soir newspaper, rejected the Festina star's denials, claiming his defence was incredible since the test results were overwhelming.
He accused both Virenque and team-mate Pascal Herve, who has also denied any drug taking, of being liars.
"These two were the biggest consumers. They received at least 90 to 100 injections of EPO a year," said Voet, who was arrested with Festina's ex-team boss Bruno Roussel and Belgian doctor Erik Ryckaert for breaking France's drug laws.
EPO (erithrpoietin) boosts the oxygen content in the blood and thus can boost endurance.
Voet said that Virenque and Herve - the only Festina cyclists not to acknowledge taking performance enhancing substances - also used growth hormones and cortisone.
But he added that Virenque only took drugs in preparation for the Tour de France.