Marinez was part of Oakland’s 2012 J2 class, and though he has been a two-way player in the past, he was used exclusively as in infielder the last six years. An underwhelming performer both offensively and defensively, Marinez showed an inability to refine his approach, and he’s struggled hitting with any power or getting on base. The one tool that has consistently impressed has been his cannon of an arm from the hot corner. After a rocky 2018 campaign that also saw Marinez serve an 80-game suspension for a banned substance, the A’s began transitioning him to the bullpen during instructs.
On the mound, Marinez showcases a big fastball and easy arm-action, though the overall mechanics are raw. Delivering the ball out of a low three-quarters slot, he has poor extension and hip/shoulder separation, causing him to fly open early and have issues finishing on-line after release. The fastball could be a plus pitch, sitting between 94-to-96 mph (touching 98) with late armside life. Despite the raw mechanics, Marinez showed solid fastball command, with his misses mostly to his gloveside. His curveball sits between 79-to-81 mph with sharp 12-to-6 bite. Given his limited time on the mound, Marinez’ ability to both land his breaking ball and bury it for chases is impressive. The changeup is his least developed pitch, sitting 87-to-89 mph with inconsistent armspeed. There’s a chance Marinez naturally will improve his third pitch as his mechanics iron out with more time spent working as a pitcher.
It appears as though Oakland has moved Marinez to the mound full-time, and he’ll be an interesting name to follow in 2019. He’s the definition of a high-risk prospect with tons of variance as to how the pitching experiment will finish. That said, if he can clean up his delivery and refine smaller aspects of his repertoire, the upside is a serviceable big league ‘pen piece with a fastball/curveball combo that misses bats.