Lefty Hopper vs. Al Mahon — Career Comparison

On the career pitching numbers, Lefty Hopper posted a stronger line than Al Mahon. Lefty Hopper posted stronger numbers in ERA (4.91 vs 22.85) and WHIP (1.727 vs 4.154). By the career numbers, Lefty Hopper 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.