University of Oklahoma pitcher Jonathan Gray, who is expected to be a top five pick in the MLB Draft later this week, tested positive for Adderall during baseball's predraft drug testing program, reports ESPN.com.
Baseball's Rule 4 draft is Thursday.
The Joint Drug Agreement between Major League Baseball and its players' union bans Adderall use without an exemption and more than 110 players were granted exemptions in 2012.
Gray, a 6-foot 4-inch right-hander, is second among Division I starters in strikeouts this season with 138, and has a 1.59 ERA in 119 innings heading into this weekend's playoff super-regional against LSU in Baton Rouge, La.
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The positive test will not result in a suspension, but will make Gray subject to additional follow-up testing once he begins his pro career, according to a source with Major League Baseball. Adderall comprises salts of two amphetamines and is banned by MLB unless the player has a valid therapeutic use exemption. Multiple sources indicated that Gray did not have a prescription for the drug.