NEW YORK (AP) — Free agent pitcher Tyler Alexander has been suspended 100 games and St. Louis infielder Luke Doyle 50 games for violations of baseball's minor league drug program.

Alexander, a 24-year-old left-hander, had a third positive test for a drug of abuse, the commissioner's office said Friday. While in the Milwaukee organization, he was suspended for 50 games in January 2015. He did not pitch last season.

Doyle, 20, tested positive for amphetamine, a banned stimulant. He hit .207 with three homers and 25 RBIs last year for rookie-level Johnson City of the Appalachian League.

Twenty-one players have been suspended this year for violations of the minor league program.