Feb 17, 2014; Jupiter, FL, USA; A detail shot of St. Louis Cardinals batting equipment is seen during spring training at Roger Dean Stadium. Mandatory Credit: Steve Mitchell-USA TODAY Sports Steve Mitchell USA TODAY Sports

The St. Louis Cardinals were looking forward to top pitching prospect Alex Reyes showing up sometime next season for his MLB debut, but the 21-year-old's drug suspension earlier this week could have thrown a wrench into those plans.

On Monday, it was announced that Reyes was hit with a 50-game suspension after testing positive for a 'drug of abuse' for the second time.

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MLB.com's Jennifer Langosch reported that Reyes and his agent provided MLB.com with a statement, in which it was revealed the 'drug of abuse' was marijuana.

On his Twitter page, Reyes apologized to the organization and Cardinals fans for this development:

As a result of his suspension, Reyes' tenure in the Arizona Fall League came to an abrupt end and he'll return home to the Dominican Republic.

In speaking with Langosch, Cardinals general manager John Mozeliak admitted that Reyes' suspension will impact if and when he shows up on the Cards' big-league roster in 2016:

"Clearly it's disappointing," Mozeliak said on Monday. "You look at how well he was pitching this last year and having the success that he was having in the Fall League, his opportunities at the Major League level would have been very high. This is definitely a setback. As he works through his suspension, he can work out at our complex and participate in extended [spring training], but it's definitely going to slow him down."

As for his upside, the Cardinals expect big things from Reyes. At the Class A Advanced and Double-A levels in 2015, Reyes held hitters to a .197 average and posted a 2.97 ERA in just over 101 innings of work.