Luis Heredia

Heredia, 19, advanced to Low-A West Virginia in 2013 after seeing action in the Gulf Coast League and rookie ball his first two campaigns. His performance with West Virginia wasn't bad, but the organization needs to see more from the $2.6 million international-signing bonus baby, as he went 7-3 with a 3.05 ERA and 1.37 WHIP in 65 innings. Heredia, who is listed as a 6-foot-7, 220-pound righty, hasn't shown much more than the low-90s fastball he flashed as a 16-year-old. He's been passed by other prospects in the organization and his fitness level isn't as good as it could be. Heredia is still in the early stages of his career, but he has the makings of a bust if he doesn't begin to put the pieces together soon.

The Pirates treated their baby-faced 17-year-old with kid gloves in his 2011 pro debut, restricting his longest outing to four innings (in 11 starts). His fastball already sits in the low-90s as the team works to refine his mechanics and secondary pitches. It wouldn't be surprising to see the 6-foot-6 righty spend another season in rookie ball. He's a top prospect in keeper leagues that allow owners to stash players for upward of three or four seasons.

Heredia comes to the Pittsburgh organization as part of the elite pitching trio procured in 2010, along with Jameson Taillon and Stetson Allie. Years away from maturing into a big league pitcher at just 16, Heredia was thought to be one of the top international free agent signings last summer. The 6-foot-6 right-hander throws in the mid-90s and the organization is hopeful he continues to get stronger as he ages and his body matures. Dynasty leaguers might want to jump on Heredia, but fantasy owners with short-term horizons can safely pass over the young Mexican hurler.