Major League Baseball said in a statement that it suspended Yankees right-handed pitcher Daniel Marten for violating the minor-league drug prevention and treatment program Monday.
Marten, who's on the Gulf Coast League East roster, will serve a 20-game ban.
The league didn't specify how Marten violated the program.
Marten, 21, pitched in just three professional games in 2018. In 2017, he went 3-4 with a 4.18 ERA in 16 games and 14 starts on the Yankees' Dominican Summer League team.
MLB added that Griffin Conine, a Blue Jays minor-league outfielder, was suspended 50 games for testing positive for ritalinic acid and violating the program.