RHP Zack Showalter
Zack Showalter, acquired in the Jack Flaherty trade, is a perfect example of why this list isn't a ranking of these players' ceilings or talent levels. Showalter may have one of the highest ceilings of anyone in this bunch. At just 19, he's already pitching in full-season ball; and he's pitching well. He has the potential to be a front-of-the-rotation starter and is already missing bats at an above-average rate. He has 41 strikeouts in just 30 innings, to go with a 2.37 ERA. Showalter is also limiting walks fairly well for a teenage pitcher. This is why he already ranks inside the Cardinals' top 30 prospects.
Showalter may have one of the best fastballs in the Cardinals' system. This gives him a very high floor. His other pitches aren't as far along, but they show early potential as well. If Showalter is unable to develop a changeup or a second breaking ball, he may become a reliever. If he goes this route, he is likely to move more quickly. The Cardinals have fast-tracked relievers with good fastballs. Perhaps he could be in St. Louis by 2026, maybe the end of 2025 if the Cardinals need bullpen help badly enough.
But Showalter has a high enough ceiling that the Cardinals will try to develop him as a starter. His fastball is that enticing. In this scenario, 2025 is out of the question and 2026 is unlikely. He could be a rotation member by 2027. Thus, even with his high ceiling and exciting talent, Showalter ranks near the bottom of this list. He does, however, possess the potential to leapfrog several names above him.