Reference

Kimo Leopoldo, a mixed martial arts fighter, failed a drug test before his scheduled fight against Bas Rutten due to testing positive for Stanozolol, an anabolic steroid. This test result was revealed just two days before the event at WFA: King of the Streets in 2006. The positive result led to Kimo being removed from the fight, and he was subsequently replaced by Ruben Villareal, who faced Rutten.

Kimo explained that the presence of banned substances was partly due to prescribed medication he was taking for a knee surgery he had previously undergone. However, the specific presence of Stanozolol indicated the use of performance-enhancing drugs, which are banned substances in professional fighting source source.

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