Billy Koch vs. Zack Weiss — Career Comparison

Looking at the career totals, Billy Koch and Zack Weiss are fairly close on the surface numbers. Billy Koch posted stronger numbers in ERA (3.89 vs 4.61) and home runs allowed (0.91 per nine innings vs 2.63). Zack Weiss had the advantage in WHIP (1.280 vs 1.466). By the career numbers, Billy Koch 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.