Mark Mercer vs. Steve Ziem — Career Comparison

Looking at the career totals, Mark Mercer and Steve Ziem are fairly close on the surface numbers. Mark Mercer posted stronger numbers in ERA (4.7 vs 7.71) and WHIP (1.826 vs 2.143). Steve Ziem had the advantage in home runs allowed (0 per nine innings vs 1.17). By the career numbers, Mark 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.