Luis Castillo vs. Emmett O'Neill — Career Comparison

Looking at the career totals, Luis Castillo and Emmett O'Neill are fairly close on the surface numbers. Luis Castillo posted stronger numbers in ERA (3.55 vs 4.76) and WHIP (1.183 vs 1.709). Emmett O'Neill had the advantage in home runs allowed (0.35 per nine innings vs 1.11). By the career numbers, Luis Castillo 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.