Former home run king Mark McGwire's attempt to maintain a low profile is failing, courtesy of his young brother.

Jay McGwire has come out swinging against his older sibling, claiming he was the reason Mark got involved in steroids.

According to the web site deadspin.com, Jay McGwire has written a yet-to-be-published book about the use of steroids by Mark McGwire, who hit 70 homers in 1998 to shatter Roger Maris' long-standing record.

Jay McGwire, who is estranged from Mark, offered his reasons for writing the book about his brother, who has shunned the public spotlight since an ill-fated appearance at a congressional
hearing in March 2005.

"Mark is a man I think most would like to forgive because his reason wasn't nefarious — it was for survival," Jay McGwire wrote. "My bringing the truth to surface about Mark is out of love. I want Mark to live in truth to see the light, to come to repentance so he can live in freedom — which is the only way to live."

Mark McGwire came under intense scrutiny in the past years for his alleged use of steroids, which were detailed by former teammate Jose Canseco in his book "Juiced: Wild Times, Rampant 'Roids, Smash Hits & How Baseball Got Big."

Although Canseco wrote that McGwire's steroid use dated to the 1980s and that he personally injected him, Jay McGwire refuted the claim, saying his brother "took the plunge" after Jay won a California bodybuilding contest in 1994.

"I would be shocked if Mark did something like what Jose Canseco claimed happened back in the early years," the manuscript said. "(Mark) began to use, but in low dosages so he wouldn't lift his way out of baseball. Deca-Durabolin helped with his joint problems and recovery, while growth hormone helped his strength, making him leaner in the process.

"I became the first person to inject him, like most first-timers he couldn't plunge in the needle himself. Later a girlfriend injected him."

In the wake of the steroid allegations, Mark McGwire - then retired - appeared along with a handful of players at a congressional hearing on steroids and refused to answer questions about whether he ever used performance-enhancing drugs.

"I'm not here to talk about the past. I'm here to be positive about this subject," McGwire told the committee.

McGwire was reviled from coast-to-coast following the hearings and since has all but disappeared from the public eye.

His refusal to address the steroids issue has been a major factor in his failure to earn induction into the Baseball Hall of Fame despite swatting 583 home runs.

Jay McGwire said his brother was a victim of poor legal counsel.

"I thought he received some bad advice from the attorneys on that tack," he said. "I sat there hoping he would confess. Even though we'd had a falling out, I felt for Mark; he took a beating that day. Had he just taken the same route as Jason Giambi or Andy Pettitte, and said he was sorry, nobody would be worried about what he did today. He didn't. Still, on TV that day, I didn't want to see him mess up. I was pulling for him."

During his highly publicized home run chase in 1998, a reporter discovered androstenedione - an over-the-counter supplement in Mark McGwire's locker. The slugger admitted to using the substance, which led to speculation it was masking his steroid use.

Jay McGwire wrote that he directed his brother to start using the supplement.

"Mark had reached a level where he did not need to get any stronger and he couldn't afford to add any more weight," he wrote. "So I directed him to androstenedione testosterone booster, which is non-hormonal ... and works naturally with your body.

"Using andro allowed Mark to avoid all the potential adverse side effects that could occur from using anabolic steroids, such as water retention, hair loss, and liver, heart, or kidney stress."

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Jay McGwire said that the brothers' relationship became strained during a family incident, claiming Mark became enraged when Jay's stepson caused him to spill coffee on himself. He alleged that Mark swatted his stepson's butt, which led to his wife refusing to attend Mark's upcoming wedding.

The youngest McGwire brother added that his reason for writing the book, in essence, was to clear his conscience.

"Who knows what might have happened if I didn't get Mark involved with all the training, supplements, the right foods, steroids, and HGH," he wrote. "He would not have broken any records and the Congressional Hearings would have gone on without him. Maybe Barry Bonds wouldn't have ever gotten involved with the stuff, either.

"Mark McGwire might have gone silently into the night long before breaking Roger Maris' home run record. But that's just not the way it went down, so we'll never know. But at least I feel better about setting the record straight."

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