Art Mahaffey vs. Michael Mercado — Career Comparison

On the career pitching numbers, Art Mahaffey posted a stronger line than Michael Mercado. Art Mahaffey posted stronger numbers in ERA (4.17 vs 11.81) and WHIP (1.351 vs 2.250). By the career numbers, Art Mahaffey 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.