2007 – Rick Guttormson of the Softbank Hawks becomes the first player in the history of Nippon Pro Baseball to be suspended for a positive banned-substance test. Guttormson tested positively for Finasteride, which is known as a masking agent for steroids. NPB instituted its steroid policy this year.

This Day In Baseball

On August 10, 2007 — 2007 – Rick Guttormson of the Softbank Hawks becomes the first player in the history of Nippon Pro Baseball to be suspended for a positive banned-substance test. Guttormson tested positively for Finasteride, which is known as a masking agent for steroids. NPB instituted its steroid policy this year.

Source:
Baseball Reference August 10
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