Arthur: Mutating roles and no relief

From SABR member Rob Arthur at Baseball Prospectus on April 26, 2019:

In recent years, baseball fans have become inured to both the greatness and commonness of relief pitchers. It’s not atypical for some guy you’ve never heard of with a funky arm action, a wicked slider, and high-90s heat to step out of the bullpen and strike out the side. We live in an era of dominant relief pitching, where the eighth and ninth innings often seem like foregone conclusions.

Or at least we used to. The past few seasons have seen the role of relievers mutating rapidly, with the traditional late-inning specialists called upon to take on more work in longer outings and sometimes even to open up games. As a result, reliever performance has taken a major hit, and for the first time since 1973, relievers currently have a worse league-wide ERA than starters.


Granted, it’s still very early in the season, and the difference between relievers and starters could reverse itself this summer. But the trend is certainly no single-month outlier: 2018 featured the lowest difference in starter-minus-reliever ERA since 1979. It also had the most blown saves since 2008.


Read the full article here:

Originally published: April 26, 2019. Last Updated: April 26, 2019.