Jack Aker vs. Bob Macdonald — Career Comparison

The numbers give Bob Macdonald a clear advantage over Jack Aker across the core pitching metrics. Bob Macdonald led in home run suppression (HR9+ 90 vs 76), run prevention (ERA+ 101 vs 89), and skill-based run prevention (DICE+ 94 vs 88). Jack Aker held the edge in walk avoidance (BB%+ 100 vs 100). Bob Macdonald was the better reliever — the numbers make that case clearly.