Hayden Birdsong vs. Billy Muffett — Career Comparison

On the career pitching numbers, Billy Muffett posted a stronger line than Hayden Birdsong. Billy Muffett posted stronger numbers in ERA (4.33 vs 4.77) and home runs allowed (0.91 per nine innings vs 1.37). By the career numbers, Billy Muffett 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.