Michael Kopech, a first-round pick for the Red Sox in 2014, has been suspended 50 games after a positive test for the stimulant Oxilofrine, MLB announced Thursday.
Kopech was pitching for Single-A Greenville with a 2.63 ERA and 70:27 K:BB ratio in 65 innings as a starter. The team has 50 games remaining this season.
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The 19-year-old right-hander was drafted with the 33rd pick Boston received as compensation when outfielder Jacoby Ellsbury signed with the Yankees in free agency.
Oxilofrine is an amphetamine that can be used to promote weight loss and increase adrenaline. World-class sprinters Tyson Gay and Asafa Powell also tested positive for the substance in 2013.