
Justin Martinez is a fantasy baseball SP prospect sleeper and minor leaguer to know. Read our MLB prospects outlooks for fantasy baseball rookies and call-ups.
PROSPECT: Justin Martinez, SP, Arizona Diamondbacks
ANALYSIS: When looking at a pitcher that has a 21.60 ERA, dynasty league owners typically check right out. However, the 21-year-old Martinez has really flashed outstanding raw stuff – it’s just a matter of getting it in the zone consistently.
Originally signed in 2018 by the Diamondbacks out of the Dominican Republic, Martinez has been pumping triple-digit fastballs and using a hard slider and a split-finger fastball to offset the heater. The issue has always been control, as he has recorded a 10%+ walk rate at nearly every level.
This past week, Martinez made three appearances, totaling 1 2/3 innings. He walked nine and struck out four in that time, allowing six runs. However, he also generated 11 swings and misses on the week, which is a sign of just how hard it is for hitters to make contact on him when he can locate the ball.
VERDICT: No need to rush for Martinez in any format, but without a clear closer in Arizona, if he can even get his walk rate to his typical career norm, he could be fast-tracked for the role with the Diamondbacks by season end. Watch and pounce if he’s given a shot.
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