Zach Day vs. Bill Williams — Career Comparison

Looking at the career totals, Zach Day and Bill Williams are fairly close on the surface numbers. Zach Day posted stronger numbers in ERA (4.66 vs 5.06) and home runs allowed (0.85 per nine innings vs 1.69). Bill Williams had the advantage in WHIP (1.313 vs 1.554). By the career numbers, Zach Day 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.