NEW YORK (AP) - Mark McGwire's youngest brother says in a book proposal that he injected the former baseball star with steroids, according to deadspin.com.

Jay McGwire is circulating a manuscript titled "The McGwire Family Secret: The Truth About Steroids, A Slugger and Ultimate Redemption," the web site reported Wednesday.

Jay McGwire is a body builder. He says his brother started using steroids in 1994.

Jay McGwire has a strained relationship with his brother. He could not be reached for comment Thursday.

Mark McGwire repeatedly has denied using illegal performance-enhancing drugs. When he testified under oath before Congress in 2005, however, he wouldn't discuss whether he did.

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