SAN FRANCISCO – Victor Conte was sentenced to four months in prison and four months’ home confinement yesterday for his role as the mastermind in a scheme to provide pro athletes with undetectable banned drugs.

Conte, who negotiated a plea deal with federal prosecutors, started the Bay Area Laboratory Co-Operative. The lab, according to court records, counted dozens of prominent athletes among its clients, including baseball’s Barry Bonds and Jason Giambi and Olympic track and field star Marion Jones.

Greg Anderson, Bonds’s trainer and friend since childhood, was sentenced to three months behind bars and three months in home confinement after pleading guilty to money laundering and a steroid distribution charge.

James Valente, Balco’s vice president, was sentenced to probation after pleading guilty to reduced charges of steroid distribution.

Outside the courthouse, Conte read a statement saying he wanted to rid the sporting world of steroids.

“I’ve decided to direct my knowledge, experience, and determination toward making sports more honorable for the athletes and fans,” Conte said.

The case prompted pro sports to stiffen steroid policies and thrust performance-enhancing drugs into the spotlight. THG, a steroid uncovered in the investigation, is now banned throughout sports.

Conte pleaded guilty in July to money laundering and a steroid distribution charge; dozens of counts were dropped as part of his plea deal. Anderson and Conte, who remain free on bond, are scheduled to surrender to prison authorities December 1.

U.S. Attorney Kevin Ryan in San Francisco has said the plea deals, which some anti-doping officials have criticized as too lenient, were spurred in part by weak steroid laws and by the fact that some of the chemicals were not banned at the time.

Track coach Remi Korchemny, the fourth and final defendant in the case, is expected to get probation at a later sentencing date.

Meanwhile, officials are taking aim at the alleged Balco suppliers. Last month, federal agents raided a laboratory in Champaign, Ill., headed by Patrick Arnold, who’s known for introducing the steroid precursor androstenedione in America. Andro came to public attention in 1998 when Mark McGwire said he used it when breaking the single-season home run record.

Court records suggested Arnold supplied Balco with THG, which was known as “the clear.”

The two dozen or so athletes who appeared before a grand jury in 2003, including Bonds, Giambi, and Jones, were not targets of the steroid probe. They were granted immunity in exchange for their testimony.

In other steroid-related news yesterday, Mets reliever Felix Heredia was suspended for the first 10 days of next season for violating baseball’s steroids policy. Heredia became the 11th major league player suspended for steroids.

Traded from the Yankees to the Mets during the off-season, Heredia appeared in only three games before going on the disabled list in April with a strained left thumb. Doctors then found an aneurysm in his left shoulder after he began having circulation problems and he missed the rest of the season following surgery.

Heredia is 28-19 with six saves in 511 career games – all but two in relief.