Jack Aker vs. Michael Kopech — Career Comparison

Michael Kopech built a career as a starting pitcher and Jack Aker as a reliever — different jobs with different demands — but on the metrics that apply to both, a comparison is still worth making. Michael Kopech led in strikeout rate (K%+ 100 vs 86), home run suppression (HR9+ 83 vs 76), and run prevention (ERA+ 95 vs 89). Jack Aker held the edge in walk avoidance (BB%+ 100 vs 58). Keeping the role difference in mind, the edge still goes to Michael Kopech.