Oklahoma pitcher Jonathan Gray, the No. 2 prospect heading into this week's major league draft, tested positive for Adderall during the predraft drug testing program, according to multiple sources.

The positive test will not result in a suspension, but will make Gray subject to additional follow-up testing once he begins his professional career.

Adderall 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.