Delvin Perez, a top draft prospect out of Puerto Rico, is sliding down mock drafts after a recent failed drug test.

Perez, who will turn 18 in November, has drawn interest from Major League clubs as a high first round pick.

Baseball America is reporting that Perez tested positive for "an undisclosed performance enhancer."

The expectation is that he'll still be selected in the first round due to his enticing talent level.