It's usually pretty hard to take athletes seriously when they claim that their positive PED test was due to a tainted supplement. It's easy to think that even if it were the case, then they probably should've known better than to deal with a suspect company.
The case of David Vobora (LB, Rams) makes it hard NOT to have sympathy for the player, though:
http://sports.espn.go.com/nfl/news/story?id=6680714The company making the spray he used is called the "Anti-Steroid Program LLC" and was endorsed by his coach and at least one team mate. He also did his own due diligence by calling the League hotline set up for that exact purpose.
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