I've seen a lot of hype for the pitcher's stat wOBA Against lately, and I have to say it's entirely warranted. I've always felt that it is one of the better stats to use for pitchers, but especially when evaluating a change of state of some kind.
For instance, if you were concerned a pitcher might be having trouble locating from the stretch, you might not want to focus solely on FIP in your analysis. If the pitcher's velocity, location, or movement is off then you'd want to include batted balls in your investigation as well. You could try looking at FIP and BABIP at the same time, but that might not give you the whole picture. Using ERA or RA9 won't work because you are splitting up base states. You could even try OPS against, which is offered at Baseball Reference, but you'll likely hear about it.
So wOBA Against is a great solution. (If you're not familiar with what wOBA actually is, you can read about it here.)
Problem is, there is no good place to find it. FanGraphs reportedly has wOBA Against on its to-do list, but it is not currently available on the site without some considerable effort.
So until then, I thought we could take a sneak peak at the wOBA against leaderboards for recent seasons.
I queried Retrosheet for the top ten pitching seasons by wOBA Against with at least 100 batters faced in the regular season. Before we continue, however, I want you to pause for a moment and take your best guess at which name is going to appear at the top of this list. Craig Kimbrel in his invincible 2012 season? Nope, that's second. Eric Gange and his unreal 2003? Third. The Sandman? Nope.
Lowest wOBA Against 2002-2012
Obviously Adams put up some terrific peripherals that year, including a phenomenal 33 percent strikeout rate along with an impressive walk rate of just six percent. He faced a expected amount of left-handers so his good fortune wasn't necessarily platoon-related. PetCo park always has a dandy way of preventing the longball, and after facing 133 batters, Adams allowed just one of them to put the ball in the seats that year.
But Adams also benefitted from an other-worldly .159 BABIP in front of a Padres defense that was eight runs below average that season (per UZR).
Along with the expected showings of Rivera and Gagne, we have a slew of hard-throwing relievers in career seasons, four of which occurred just recently in 2012-- Rodney and McGee, both with the Rays, Street, and Kimbrel.
Part of this can be blamed on the recent pitcher's era into which baseball has entered in the last few years. Even though the component weights are adjusted season-to-season, wOBA does not adjust to league average. (For that we would use pitcher's wRC+ Against, which hopefully I can publish next week some time.)
Incidentally, Adams' excelsior 2009 is also the best season by wOBA Against dating back to 1950 as well. Dennis Eckersley's fantastic 1990 season comes close, with a microscopic wOBA Against of just .176 after 262 batters faced, And Cisco Carlos wasn't too far behind with a .181 in 1967.
Among pitchers with at least 500 batters faced as a starter, the leaders in wOBA Against are little more than the usual suspects.
Lowest wOBA Against 2002-2012 (min 500 BF)
No surprise that the magnificent Pedro Martinez has two of the ten best pitching seasons in recent memory by this method. But his other-worldly 2000 season, in which he won the Cy Young award and posted 12 WAR, also ranks as the greatest season for starting pitchers since 1950 by wOBA Against.
Pedro's wOBA Against of just .213 beats out some of the finest pitching performances of the half-century, including Maddux's 1995 (.216), Gibson's '68 (.218) and Koufax's '63 (.224):
Lowest wOBA Against 1950-2012 (min 500 BF)
If you'd like to evaluate a particular pitcher or group of pitchers using wOBA Against on your own, you are welcome to the full google doc with all 5,000+ pitching seasons from 2002-2012: LINK.
If you'd like any other fields added to the spreadsheet I will happily oblige you.
Thanks to Fangraphs, Baseball Heat Maps, and Retrosheet for the data.