Riley O'Brien vs. Rich Thompson — Career Comparison

Looking at the career totals, Riley O'Brien and Rich Thompson are fairly close on the surface numbers. Riley O'Brien posted stronger numbers in ERA (3.55 vs 4.21) and home runs allowed (0.93 per nine innings vs 1.55). Rich Thompson had the advantage in WHIP (1.357 vs 1.457). By the career numbers, Riley O'Brien 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.