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Jason Grimsley was asked by federal agents to wear a listening device to gather incriminating evidence against Barry Bonds but refused, an attorney for the former Arizona Diamondbacks pitcher said.

"It was a specific effort to target Bonds," Edward Novak told the Arizona Republic. "We were told that Jason's cooperation was necessary to their case."

Novak also told the newspaper that Grimsley denied volunteering names of fellow players, as reported in court documents released Tuesday. Instead, federal agents asked Grimsley what he knew about the illegal drug habits of specific athletes, such as former Mets and Phillies outfielder Lenny Dykstra.

"They asked him specifically about Barry Bonds, and Jason said he didn't know Bonds well and didn't know if he did or didn't use drugs," Novak told the paper for a story Thursday.

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The attorney said investigators asked Grimsley whether he was close to any San Francisco Giants players who might talk about Bonds. Grimsley refused, Novak said, and told investigators "baseball players don't go around talking about who is using and who isn't."

Novak did not immediately return after-hours calls left Thursday at his office by The Associated Press.

Meanwhile, Bonds' ex-mistress, Kimberly Bell, was advised by federal authorities not to cooperate with baseball's investigation into steroid use in baseball because of a "pending criminal proceeding," her lawyer told the New York Times for a Friday story.

The lawyer, Martin Garbus, sent a letter dated Thursday to inform former Senate Majority Leader George Mitchell, hired by commissioner Bud Selig in March to investigate steroids in baseball, of Bell's decision.

"The Federal Bureau of Investigation personnel involved in the San Francisco investigation of Barry Bonds have advised my client that you cannot compel her to testify and that she should not testify because of the pending criminal proceeding," Garbus wrote in a letter obtained by the newspaper.

Bell has claimed that Bonds confided in her that he used steroids.

The letter could indicate that federal investigators are pursuing perjury charges and possibly additional charges of financial malfeasance against Bonds.

Bonds, asked about Grimsley's situation before the Giants' game in San Francisco on Thursday, refused to comment.

The New York Post reported Friday that Bonds' attorney, Michael Rains, received a letter from Mitchell last month saying that he wants to interview the Giants slugger as part of baseball's investigation.

"They sent me a letter announcing the investigation and that they would want to talk to Barry at some future date," Rains told the newspaper. "They also said they would want some production of documents then."

Rains told the Post that he has advised Bonds to cooperate as much as he can legally.

While Grimsley's lawyer said the right-hander disputes much of what was in the affidavit released Tuesday, he did not deny past use of performance-enhancing drugs. "He has admitted his past steroid use," Novak said.

Arizona released Grimsley on Wednesday, a day after his home was searched by federal agents following his admission he used human growth hormone, steroids and amphetamines. Grimsley's agent, Joe Bick, told the AP the revelations were likely to end the 38-year-old reliever's career.

Thirteen federal agents searched Grimsley's home in Scottsdale, Ariz., for six hours Tuesday, but didn't reveal what was found. Investigators who cracked the BALCO steroid scandal in San Francisco said Grimsley initially cooperated in the probe but withdrew his assistance in April, prompting Tuesday's search.

An affadavit in support of that raid said agents had tracked a package containing human growth hormone to Grimsley's house April 19 and confronted him at his door. Novak said agents coerced Grimsley into cooperating to avoid being embarrassed in front of friends and family members at the home.

"They specifically told him, 'Don't call a lawyer,'" Novak said. "They let him know that if he didn't cooperate, they basically would terrorize his family and come in with guns drawn and lights flashing."

The U.S. Attorney's Office for the Northern District of California said in a statement Wednesday that the search was "conducted in an entirely appropriate and legal fashion."

Grimsley gave his initial statement to authorities, detailing his "receipt and use of anabolic steroids, amphetamines and human growth hormone over the last several years," but said he went exclusively with HGH when baseball's testing program began.

The document said he also identified several other players who used or supplied the drugs, though their names were blacked out. But he hired Novak a few days after speaking with investigators and refused further cooperation.

A federal grand jury in San Francisco is investigating whether Bonds lied under oath about using the performance-enhancing drug known as "the clear" during his grand jury testimony that led to the indictment of four people connected to BALCO.

Commissioner Bud Selig had no comment on the specifics of Grimsley's case.

Grimsley was 1-2 with a 4.88 ERA in 19 games as a long reliever this season, his first with Arizona.

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