Mike Hartley vs. Slim McGrew — Career Comparison

Looking at the career totals, Mike Hartley and Slim McGrew are fairly close on the surface numbers. Mike Hartley posted stronger numbers in ERA (3.7 vs 6.6) and WHIP (1.396 vs 1.900). Slim McGrew had the advantage in home runs allowed (0.3 per nine innings vs 0.79). By the career numbers, Mike Hartley 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.