JaMarcus Russell admitted to ESPN that he tested positive for codeine after being selected as the No. 1 draft pick in 2007 by the Oakland Raiders.
"I missed all of training camp, so I didn't get tested when all the other guys got tested," said the former Raiders quarterback. "I had a prescription from a doctor, but it wasn't the team doctor."
Russell also said he used codeine without a prescription, but denied ever having a drug problem.
Russell, who was arrested and charged last month for possession of codeine syrup, held out of training camp in 2007 over a contract dispute.
According to Russell, the Raiders has asked him about drug use during his rookie year.
"Around the time when I first got there or a year after I got there," Russell said. "They said they were gettin' word in the streets about me using drugs. Then, one of the doctors came to me."
He also said he hasn't used codeine in three years.
Oakland released Russell in May. The Raiders only won seven games in three years with Russell as the starting quarterback.