Jonathan Aro vs. Pop Williams — Career Comparison

On the career pitching numbers, Pop Williams posted a stronger line than Jonathan Aro. Pop Williams posted stronger numbers in ERA (3.17 vs 6.55) and WHIP (1.395 vs 1.909). By the career numbers, Pop Williams had the better of this comparison — though ERA and WHIP alone don't account for era, park factors, or the defenses each pitcher worked behind.