Ryan Mattheus vs. Jim Peterson — Career Comparison

On the career pitching numbers, Ryan Mattheus posted a stronger line than Jim Peterson. Ryan Mattheus posted stronger numbers in ERA (3.72 vs 5.27) and WHIP (1.462 vs 1.665). By the career numbers, Ryan Mattheus 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.