Michael Petersen vs. Mason Thompson — Career Comparison

Looking at the career totals, Michael Petersen and Mason Thompson are fairly close on the surface numbers. Michael Petersen posted stronger numbers in ERA (5.02 vs 5.21) and WHIP (1.593 vs 1.667). Mason Thompson had the advantage in home runs allowed (0.87 per nine innings vs 1.43). By the career numbers, Michael Petersen 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.