Alcantara has an electric arm, regularly reaching triple-digits with his fastball, and has made developmental strides with both his changeup and curveball thus far in 2016. The quality of his stuff has regularly overpowered Midwest League opponents, and has powered an impressive strikeout rate of 12.1 Ks-per-9. As is often the case with young power arms, Alcantara also struggles to control his stuff, often missing his spots and regularly slipping into bouts of legitimate wildness, as evidenced by both his 5.0 BBs-per-9 rate, and the surprisingly high rate at which he allows base hits (almost one per inning).

In Tuesday’s start against Beloit, Alcantara wowed with his pure stuff, sitting comfortably in the 94-to-98 mph range and hitting 100 mph on multiple occasions, including the second pitch of the game, and again during his last inning of work (the fifth). His heater gets straight at higher velocities, and particularly so up in the zone, but he also flashed a little bit of arm-side life in the 94-to-96 mph velo belt.

His second-best offering on the start was a quality changeup with arm-side dive, sitting 88-to-92 mph. Alcantara shows solid deception, with the offering coming both out of an arm slot and on a trajectory that dovetail with the heater. He was more effective with the offering early on, shifting over to a focus on the breaking ball after the first couple of innings of work. The pitch projects as a potential plus offering with legit swing-and-miss action.

His curveball flashed plus with hard 11-to-5 break, sitting in the low 80s. It worked as an early-count offering for a strike, and also as a chase pitch when working ahead. There is inconsistency in his execution still, leading to soft versions of the breaker that float up and to his arm side, as well as hard and firm darts in the dirt. He spins the pitch well, overall, and the offering projects as a future weapon that could grade out as above average or better at maturity.

Overall, Alcantara is still a little too timid with his stuff, though he should learn to throw with more confidence as he continues to refine his execution, and as he finds more consistency across his arsenal. He flashed some feel for sequencing, particularly working backwards off of his changeup, and the body works well enough that there is reason to believe both the control and the command will improve with reps. It’s an impressive arm that could grow into a legit front-end starter at maturity, but there is a lot of developmental ground to cover before the Dominican product can reach that lofty upside.