George O'Donnell vs. Mark Prior — Career Comparison

Looking at the career totals, George O'Donnell and Mark Prior are fairly close on the surface numbers. Mark Prior posted stronger numbers in ERA (3.51 vs 4.53) and WHIP (1.240 vs 1.443). George O'Donnell had the advantage in home runs allowed (0.41 per nine innings vs 1.05). By the career numbers, Mark Prior 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.