PARTS UNKNOWN - Since the dawn of the 20th century, "sheepish" baseball fans have been led to believe that earned run average is the most accurate
measure of a starting pitcher's performance. Not so.
In an ironically silly attempt to protect pitchers from the defense that protects him, ERA assumes that earned runs paint a brighter picture of his
ability than total runs. Wrong.
In fact, this assumption runs contrary to the nature of the game. We need to consider more than just ERA. URA - or 'unearned run average' - must also
be accounted for. And the solution is, well, a solution:
ERA+URA=TRA.
Indeed, "total run average' is the complete statistic.
Consider that flyball pitchers like Roger Clemens and Curt Schilling generally induce hits to the outfield, where few balls are botched. Groundball
pitchers like Kevin Brown and Derek Lowe, on the other hand, typically induce hits to the infield, where most errors occur. Nothing
earth-shattering.
But here's the catch. Relative to their flyball counterparts, groundball pitchers create markedly more strain on the defense, causing fielders to
commit a greater number of errors. Earned runs being equal, they allow more total runs than their flyball counterparts.
But, due to the widespread acceptance of ERA as the standard by which all pitchers are measured, this inconsistency continues to be ignored. And -
earned runs being equal - the groundball pitcher isn't held accountable for his higher TRA. In essence, he's disproportionately protected by earned
run average.
And the numbers back it up.
Over his 18-year career, Schilling has given up the same number of unearned runs as Lowe, despite having thrown 1,705 more innings than his former Red
Sox teammate - and with a comparable ERA (3.35 to Lowe's 3.82).
How can this be? Has Schilling's defense over the years been that much better than Lowe's?
Not a chance.
The Red Sox ace has put his defense in far fewer comprising situations over the years by inducing a higher frequency of fly balls, which are easier to
field. And the strikeouts haven't hurt either.
With a career 0.20 URA, Schilling allows just one unearned run every 45 innings. Lowe, on the other hand, surrenders an unearned run every 18 innings,
"good" for a career 0.51 URA.
More importantly, comparing their career TRAs (3.55 vs. 4.33) explains what ERA simply can't: That Lowe isn't even in Schilling's league - and I'm not
talking about Lowe's offseason defection to the NL.
Of course, not all moundsmen can be categorized as groundball or flyball pitchers, but that's hardly the point. All pitchers are subject to the
fundamental bias of earned run average.
And while qualitative differences among defenses unevenly affects TRA in the short run, thirty-plus starts and 180 innings into the season, it all
evens out.
ERA has long since "earned" the trust of baseball fans. But at the end of the day, it doesn't measure up to TRA. Because it never told the "total"
story.