High Class A St. Lucie lefty Angel Calero tested positive for metabolites of Nandrolone, a performance-enhancing substance, and was suspended for 50 games. The news came late Monday afternoon via a press release by Major League Baseball.

The Mets shifted the 23-year-old Calero to the bullpen this season after an uneven campaign in 2009, in which he made 22 starts for St. Lucie. This year, he appeared in four games, going 1-1, 5.68 with 10 strikeouts and seven walks in 6 1/3 innings.

MLB also suspended Socrates Brito, a Dominican outfielder who agreed to a deal with the Diamondbacks in February. He tested positive for metabolites of Stanozolol, a performance-enhancing substance, which prompted Arizona to void his contract. They did not entirely rule out re-signing Brito, who is now a free agent.