Jamie Arnold vs. Jack Mercer — Career Comparison

Looking at the career totals, Jamie Arnold and Jack Mercer are fairly close on the surface numbers. Jack Mercer posted stronger numbers in ERA (0 vs 5.73) and home runs allowed (0 per nine innings vs 0.58). Jamie Arnold had the advantage in WHIP (1.652 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.