Single-Season Leaders for Adjusted ERA+

Baseball trivia: Single-Season Leaders for Adjusted ERA+

Given adjustments for the offensive contexts of the leagues and the ballparks in which they pitched, the pitcher with the best season since WW1 was ... Pedro Martinez in 2000. Greg Maddux has the next two on the list, followed by Bob Gibson's legendary 1968. Until you look at this chart you might not realize just how good Pedro was. He has two seasons among the top ten, and five seasons better than the best of Koufax or The Unit.

In terms of career ERA+, the three best starters of all time are (1) Pedro (2) Lefty Grove (2) Walter Johnson. Both Roy Halladay and Roy Oswalt are just out of the top ten.

If the list is expanded to include both starters and relievers, Mariano Rivera is the best of all time by a very large margin.