William Pierson vs. Mason Thompson — Career Comparison

Looking at the career totals, William Pierson and Mason Thompson are fairly close on the surface numbers. William Pierson posted stronger numbers in ERA (3.38 vs 5.21) and home runs allowed (0 per nine innings vs 0.87). Mason Thompson had the advantage in WHIP (1.667 vs 1.969). By the career numbers, William Pierson 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.