Casey Janssen vs. Pop Williams — Career Comparison

Looking at the career totals, Casey Janssen and Pop Williams are fairly close on the surface numbers. Pop Williams posted stronger numbers in ERA (3.17 vs 3.63) and home runs allowed (0.09 per nine innings vs 0.88). Casey Janssen had the advantage in WHIP (1.238 vs 1.395). By the career numbers, Pop Williams 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.