SAN FRANCISCO (AP) – A plea deal struck between a former New York Mets clubhouse employee and prosecutors could expose steroid use among dozens of current and former major league players.

Authorities have not released any names uncovered in their investigation of Kirk Radomski, who pleaded guilty Friday to distributing steroids to players for a decade. But his agreement to cooperate in the ongoing federal probe of steroids in sports likely spells doom for players counted among his clients.

As part of the plea deal signed Thursday, Radomski, 37, also agreed to testify before a grand jury, if needed, and to meet with investigators from baseball’s own steroids investigation, led by former Senate Majority Leader George Mitchell.

“We are encouraged that the U.S. Attorney has insisted Mr. Radomski cooperate with Senator George Mitchell’s investigation as a condition of the plea agreement,” MLB president Bob DuPuy said.

Mr. Mitchell issued a statement saying: “We look forward to working together with federal law enforcement toward our shared goal.”

Radomski admitted providing anabolic steroids, human growth hormone, Clenbuterol, amphetamines and other drugs to “dozens of current and former Major League Baseball players, and associates, on teams throughout Major League Baseball,” San Francisco Federal prosecutor Scott Schools said in a statement.

The names of players appeared to be blacked out of a search warrant affidavit obtained by several news organizations.

“The distribution of anabolic steroids to professional athletes cheats both the paying public and the clean athletes and is a serious crime,” Mr. Schools said. “This investigation shows that distribution of performance-enhancing drugs continues to be an issue for sport in America.”

Radomski pleaded guilty in Federal District Court to felony charges of distributing steroids and laundering money. He faces up to 25 years in prison and a $500,000 fine at his sentencing, scheduled for Sept. 7.

His lawyer, John F. Reilly of Long Island, N.Y., did not return a call for comment.

Radomski worked for the Mets for a decade, beginning in 1985, then used the contacts he made to go into business selling steroids and other drugs to ballplayers, according to his signed plea agreement.

According to court documents, Radomski became a major source of drugs for baseball players after federal investigators shut down the Bay Area Laboratory Co-Operative in Burlingame, the center of a massive drug distribution ring shut down by federal authorities in 2003. And SI.com reported cell phone numbers belonging to current and former MLB players already have been identified.

Radomski used the money to pay the mortgage on his home, which served as his base of operations for the steroids business. He made the deposits to a New York-based bank and sold steroids in person, over the phone and by mail, according to the agreement.

An FBI informant told federal agents about Radomski, the documents show. And on Dec. 7, 2005, the documents show, he received an order for steroids from someone in San Jose he believed was a friend of an earlier customer. He shipped two vials of deca-durabolin, an anabolic steroid, and testosterone to that address.

A week later, on Dec. 14, federal agents raided his house on Long Island and his dealing operation came to an end.

“A review of the deposits made into the accounts indicate numerous significant deposits from current and former Major League Baseball players, as well as some individuals affiliated with Major League Baseball players,” reads the search warrant affidavit, according to a person familiar with the affidavit who spoke on condition of anonymity because it had not been made public.

The affidavit also listed 23 checks worth more than $30,000 that federal investigators alleged were deposited by individuals associated with MLB into Radomski’s bank account between May 2003 and March 2005, the Washington Post reported.

The case is being handled by the same federal investigators who netted guilty pleas from BALCO founder Victor Conte and Barry Bonds’ personal trainer, Greg Anderson, among others. Anderson is in prison for contempt of court because he has refused to testify against Bonds in a related perjury investigation.

The New York Daily News was the first to report Radomski’s guilty plea, while SI.com, the San Jose Mercury News and the Washington Post were first to report details from the search warrant affidavit.

Howard Johnson, a Mets infielder in the 1980s and currently the team’s first-base coach, remembered Radomski.

“He was a clubhouse kid, one of several, one of the kids that were there,” Johnson said before the Mets played at Washington on Friday night.

“The conduct in question is diametrically opposed to the values and standards of the Mets organization and our owners,” the Mets said in a statement. “We are and always have been adamantly opposed to the use of performance-enhancing drugs and continue to support Major League Baseball’s efforts to eradicate any such use in our game.”

___

Associated Press Writer Lisa Leff in San Francisco and Sports Writers Howard Fendrich in Washington and Eddie Pells in Denver contributed to this report.