Report: Giants prospect Mejia receives 50-game suspension for drug violation

San Francisco Giants prospect Adalberto Mejia reportedly received a 50-game suspension Friday after testing positive for a banned stimulant, according to Alex Pavlovic of the Mercury News.

The 21-year-old left-hander emerged as one of the club's top pitching prospects over the last two seasons, and was lauded by Baseball Prospectus in January as the Giants' second-best minor leaguer.

Mejia ascended quickly through the lower levels of the minor leagues after signing with the Giants for $350,000 in 2011, reaching the Triple-A Pacific Coast League in just his second full season as a professional. The Dominican native fashioned a 4.67 ERA with a 1.39 WHIP over 108 innings for Double-A Richmond last season, posting a 2.65 strikeout-to-walk ratio over 21 starts and one relief appearance.