When Arizona released Jason Grimsley, the latest baseball player caught in the steroid scandal, baseball officials said it underscored the need for tougher drug tests.

But Diamondbacks catcher Johnny Estrada thinks players will keep looking for an edge, and the furor over Grimsley might not deter cheaters.

"No amount of testing or anything else is going to stop people from trying to cheat," Estrada said yesterday. "It’s just human nature."

Estrada spoke on the day the Diamondbacks released Grimsley, whose home was searched Tuesday by federal agents following his admission he used human growth hormone, steroids and amphetamines.

The raid - and Grimsley’s implication of other major league ballplayers - was the latest sign that widespread investigations into drug use by athletes are still active, even in the era of tougher testing.

"Clearly," U.S. Attorney Kevin Ryan said, "we’re not done."

Grimsley’s agent told The Associated Press he thought this would mark the end of the 38-year-old reliever’s career.

"My guess is Jason’s done playing," Joe Bick said in a telephone interview. "I couldn’t anticipate that he would play again, but that’s his call.

"He didn’t want to be a distraction to the team."

Diamondbacks General Manager Josh Byrnes said Grimsley asked for his unconditional release in meetings with team officials Tuesday and yesterday.

"We accepted his request," Byrnes said.

According to court documents, Grimsley failed a baseball drug test in 2003. At that time he was with the Kansas City Royals, for whom he played from 2001 to 2004.

Thirteen federal agents searched his home in Scottsdale, Ariz., for six hours Tuesday, but they would not reveal what they 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.

Authorities tracked a package containing two "kits" of human growth hormone - about a season’s supply - that was delivered at Grimsley’s house on April 19, court documents released Tuesday showed.

Moments later, agents armed with a warrant offered him an option: Cooperate with their investigation into athletes using performance-enhancing drugs, or submit to an immediate search. Grimsley agreed to be interviewed.

He continued to detail 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.

Grimsley also identified several other players who he said had used or supplied the drugs, though their names were blacked out from court documents. They included a handful of former teammates and one player he identified as one of his "better friends in baseball," adding that it was common knowledge that "Latin players" were a major source for amphetamines.

He also identified a personal fitness trainer to several major league ballplayers who once referred him to someone that later supplied him with an array of drugs.

The investigation is being run by prosecutors and authorities in San Francisco, where five Bay Area Laboratory Co-Operative defendants pleaded guilty to distributing or developing steroids. Ryan said the government’s probe will "diligently follow the evidence."

A federal grand jury in San Francisco is also investigating whether Giants slugger Barry 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.

The issue of athletes and drugs has been a constant topic in sports, heightened when Mark McGwire, Rafael Palmeiro and Sammy Sosa testified before Congress last year and further fueled by the Grimsley developments.

"It can’t be more of a distraction than it already is," New York Yankees pitcher Mike Mussina said. "Every time Barry Bonds comes up to the plate, they’re talking about it. How much longer can you keep talking about the same subject?"

Commissioner Bud Selig had no comment on the specifics of Grimsley’s case. Major League Baseball executive vice president Rob Manfred said HGH "is a problem for all sports because there is no universally accepted and validated test."

"No governing body in any sport has ever been able to discipline an athlete for the use of HGH," he said.

Grimsley’s locker was empty before Arizona’s 7-3 loss to Philadelphia at Chase Field.

Bick said "there was no negotiation" over the remainder of Grimsley’s $825,000 salary. "Released players get paid," he said.

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

Diamondbacks pitcher Terry Mulholland said Grimsley addressed his NL West-leading teammates after Tuesday’s loss to the Phillies.

Grimsley began his career with Philadelphia in 1989 and pitched for Cleveland, California, the Yankees, Kansas City, Baltimore and Arizona. He was 42-58 with a 4.77 ERA.

Grimsley has spent much of his career as a journeyman, but made headlines in 1999 when he confessed to his role in the Albert Belle corked bat caper.

Grimsley, who had been Belle’s teammate with Cleveland, admitted he worked his way through a crawl space at Comiskey Park in 1994 and dropped through the ceiling in the umpires’ room to replace the illegal bat.

"I went sky diving once, and I can compare it to that," Grimsley said at the time. "The adrenaline rush I got from that caper was just like jumping out of an airplane. It was being in a place you’re not supposed to be."

● BONDS QUESTIONABLE: Barry Bonds tweaked his left side during last weekend’s series in New York, though the San Francisco slugger initially tried to play through it.

The injury has become worse in recent days, and Bonds grimaced after a swing during Tuesday night’s 2-1 win over the Florida Marlins.

He was already scheduled for a day off yesterday for the finale of a three-game series with the Marlins, but now his status for a four-game series against his former club - the Pittsburgh Pirates - starting tonight was in question.

"I hope this is not a serious problem," Giants Manager Felipe Alou said.

Bonds went 0 for 4 with a strikeout one night after hitting his 716th career home run to move within 40 of passing home run king Hank Aaron’s 755.

"I don’t know yet," Bonds said when asked about the severity of his injury. "I was hurt from the second inning" Tuesday. "I played because I didn’t want to come out. ... I’m only concerned if somebody’s putting me in a coffin."

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