After Bilonog narrowly beat Nelson for the gold at the 2004 games, his doping sample was stored, then re-tested last year with new technology.

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Dr. DON CATLIN (Executive Officer, Anti-Doping Research Institute in Los Angeles): The fact that we're making solid progress is very, very exciting to me.

NPR: Baseball Considers Human Growth Hormone Tests

"The message to athletes is 'We're going to get you', " he declared at a briefing on anti-doping policy ahead of the Games.

BBC: Organisers talk tough on drugs