Jeremy Affeldt vs. Michael Kopech — Career Comparison

Michael Kopech built a career as a starting pitcher and Jeremy Affeldt as a reliever — different jobs with different demands — but on the metrics that apply to both, a comparison is still worth making. Jeremy Affeldt led in home run suppression (HR9+ 118 vs 83), walk avoidance (BB%+ 87 vs 58), and skill-based run prevention (DICE+ 89 vs 78). Michael Kopech held the edge in strikeout rate (K%+ 100 vs 81). Role difference aside, Jeremy Affeldt holds a clear edge on every meaningful shared measure.