David Aardsma vs. Kevin Shackelford — Career Comparison

On the career pitching numbers, David Aardsma posted a stronger line than Kevin Shackelford. David Aardsma posted stronger numbers in ERA (4.27 vs 5.35) and WHIP (1.487 vs 1.578). By the career numbers, David Aardsma 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.