Chicago White Sox right-handed pitching prospect Andre Rienzo has tested positive for metabolites of Stanozolol, a banned performance-enhancing substance, and will now serve a 50 game ban. Stanozolol is a powerful synthetic steroid and is the same substance Rafael Palmeiro tested positive for in 2005.
Rienzo is currently on the roster of the Winston-Salem Dash, a High-A affiliate. The 23 year old was signed as an 18 year old out of Sao Paulo, Brazil. He had been pitching very well for the Dash in his second season in the Carolina League. In four starts, he had pitched 25 innings giving up just 17 hits and 7 walks while striking out a league leading 31 batters. His ERA of 1.08 was third best in the league.
Rienzo largely relied on a very good fastball but his secondary pitches are still works in progress. Baseball Prospects ranked him the 11th best prospect in the organization and Baseball America ranked him the 17th best prospect.While Rienzo is not a spectacular prospect, he arguably is one of the five best pitching prospects in the White Sox minor leagues and, based on his fastball, he certainly projects as at least a possible reliever in the majors. At 23, he is old for High-A and this suspension will further slow his progress to the majors.
To my knowledge, he is the first White Sox minor leaguer to be suspended for a performance-enhancing substance. Non-prospect OF Miguel Negron was suspended in 2010 for a "drug of abuse".