Case Study: Where ERA Falls Short

During discussions about the irrelevance of won-loss records for pitchers, it's been suggested to me that ERA helps balance the equation. W-L speaks of specific clutchness while ERA describes overall performance.

The small grain of truth there is that ERA certainly is vastly superior in describing pitching performance than pitching wins and losses. Indeed, despite its inability to parse defense, relief aid and luck, ERA is still a good approximation of pitching prowess. 

A game today between Cleveland and Boston at The Fens showed how ERA can go wrong.

Former Milwaukee closer John Axford entered a 2-2 game in the bottom of the ninth inning for the Indians. Axford sported a decent ERA but an awful 27/18 K/BB tally in 28 frames. That means he's offering up two free passes every three innings to accompany 24 hits, an unsustainable number of baserunners, particularly because his HR rate is unremarkable.

Axford opened the bottom of the ninth by fanning .200-hitter Daniel Nava on a 3-2 pitch before putting AJ Pierzynski aboard on balls. He moved the winning run to second by walking Grady Sizemore before whiffing Stephen Drew on a 3-2 count. On the brink of escaping, Axford uncorked a wild pitch to advance the winning run within 30 yards of fruition. And then he walked the number nine hitter, Jackie Bradley, Jr.

Ordinarily. the odds of the batting team scoring a run with two outs and the bases loaded are roughly one in three. However, without any margin for error -- most notably a walk or HBP -- manager Terry Francona had no choice but to yank his inconsistent reliever. 

Scott Atchison replaced Axford and induced a groundout by Brady Holt, allowing the Tribe to escape unscathed. (They later won on a Nick Swisher home run in the 11th.)

And so, the box score says that John Axford successfully hurled 2/3rds of an inning of scoreless ball, lowering his ERA no matter where it stood before. Of course, there's is no such thing as 2/3rds of an inning of scoreless ball. That's like two-thirds of a crime-free life. A nine-run inning could have been 2/3rds scoreless.

John Axford walked three more batters than did Cleveland's other four relievers during their six frames of work. He drove his team to the brink of defeat, saved only by his successor. The defense played no role. There were no unearned runs to complicate the matter. But his ERA declined despite a thoroughly awful performance.

Axford, sporting a jaunty 3.21 ERA, has now allowed 21 walks and 24 hits in 29 innings. That, not his ERA, is why he is a former closer.