The rangy righty signed with the Dodgers in 2016, making his stateside debut this summer in the AZL. He pitches from a slow semi-windup that finishes clean down the mound, though his arm action is more high-maintenance. Acosta is rigid through the hand-break, causing his elbow to stay low as he pushes the ball through a three-quarters slot.
His fastball worked at 91-to-93 mph, showing natural running action from his low release point. Acosta was able to keep the heater around the zone, showing more control than in-zone command. He has the body and delivery to add a few ticks to this fastball as he fills out, likely able to make improvements in the command department as well. Acosta has an advanced feel for his changeup, showing it frequently and mixing the pitch to both righties and lefties. At 83-to-85 mph, there was plenty of velocity separation from the heater, and he was able to throw it with fastball armspeed while generating late fade action. The bottom really fell out at times; it’s his best off-speed pitch, and numerous hitters swung over the top of the changeup in my look. A 74-to-78 mph curveball flashes the potential to develop into an effective pitch, but aspects of Acosta’s arm action make it difficult to consistently find extension on the pitch.
Still just 19-years-old, Acosta’s frame, projection, and three-pitch mix all intrigue. He could develop into a prospect with more development, though he’s still raw enough that a stint in Extended Spring Training next year is likely.