Radomski, who admitted giving dozens of major leaguers steroids and human growth hormone, also was ordered to pay an $18,575 fine by U.S. District Judge Susan Illston.
He pleaded guilty in April 2007 to distributing steroids and laundering money, admitting he sold speed, steroids and HGH to players from 1995 until Dec. 14, 2005, when agents raided his Long Island, N.Y., home.
As part of his plea deal, Radomski was required to cooperate with investigators probing baseball's doping scandal. He led investigators to Brian McNamee, the former New York Yankees strength coach who claimed he injected Roger Clemens with steroids and human growth hormone at least 16 times from 1998 to 2001, an allegation the seven-time Cy Young Award winner vehemently denies.
Radomski is scheduled to testify before Congress on Wednesday along with Clemens, Andy Pettitte, Chuck Knoblauch and McNamee.