Jack Armstrong vs. Charlie Kerfeld — Career Comparison

Jack Armstrong built a career as a starting pitcher and Charlie Kerfeld as a reliever — different jobs with different demands — but on the metrics that apply to both, a comparison is still worth making. Charlie Kerfeld led in home run suppression (HR9+ 170 vs 85), run prevention (ERA+ 116 vs 89), and skill-based run prevention (DICE+ 109 vs 89). Jack Armstrong held the edge in walk avoidance (BB%+ 91 vs 81). Role difference aside, Charlie Kerfeld holds a clear edge on every meaningful shared measure.