Willie Jefferson vs. Yoshinobu Yamamoto — Career Comparison

Looking at the career totals, Willie Jefferson and Yoshinobu Yamamoto are fairly close on the surface numbers. Yoshinobu Yamamoto posted stronger numbers in ERA (2.66 vs 3.94) and WHIP (1.032 vs 1.314). Willie Jefferson had the advantage in home runs allowed (0.41 per nine innings vs 0.72). By the career numbers, Yoshinobu Yamamoto 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.