John Costello vs. Zack Weiss — Career Comparison

Looking at the career totals, John Costello and Zack Weiss are fairly close on the surface numbers. John Costello posted stronger numbers in ERA (2.97 vs 4.61) and home runs allowed (0.74 per nine innings vs 2.63). Zack Weiss had the advantage in WHIP (1.280 vs 1.395). By the career numbers, John Costello 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.