Jack Mercer vs. Erik Swanson — Career Comparison

Looking at the career totals, Jack Mercer and Erik Swanson are fairly close on the surface numbers. Jack Mercer posted stronger numbers in ERA (0 vs 4.2) and home runs allowed (0 per nine innings vs 1.66). Erik Swanson had the advantage in WHIP (1.154 vs 2.000). By the career numbers, Jack Mercer 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.