Relativity of Pitching Success
May 22, 2012
The average baseball fan is getting better about understanding the importance of ERA, WHIP, and even some of the newer metrics (BABIP, Game Score, etc) are being slowly introduced to broadcasts, but that hasn't stopped the general public from uttering such phrases as "he had a great year - I think he was 18-10" or "it was an off year for him; I think he finished under .500, like 12-13." Like it or not, people still cling to wins when judging their success of a pitcher. It's time to use some current examples to set these people straight.
For the record, I'm not simply a numbers guy. I believe that actually watching a game can add a lot of information about a player that the back of a baseball card won't tell you. However, certain advanced stats can indicate when a player is a little more or less "lucky" than others and how likely he is to revert to the mean.
Over the course of a long career, it is very unlikely that an excellent pitcher will have a bad record, nor will a poor performing pitcher be the benefactor of a great win-loss record. There is always something to be said for simply being healthy and challenging hitters long enough to stay in a game and get a win, even without the greatest underlying stats, so many wins by starters are deserved even with less than stellar performances.
The problems begin when the stellar performances occur but the wins fall by the wayside. That's where ballpark effects and a pitcher's offensive team (of which he has little to no control) start affecting the "W"s and "L"s, and that's when it's time to look at something beyond a pitcher's record. While a career will skew closer toward deserved wins (though not completely fairly as Matt Cain's career will demonstrate), over the course of a month, or even a season, the sample size is small enough for starting pitchers that the win-loss record can be unrelated to the quality of pitching.
On to the current examples:
After his first five starts this season, Ryan Dempster of the Cubs had an ERA of 1.02, a WHIP of 0.85, a strikeout rate of more than 1 per inning, and a K/BB ratio of 3.6. Every statistic indicates that Dempster pitched extremely well over that time period. Adding more specifics, Dempster left two of the games giving up 0 earned runs, once after 8 innings. His record in those 5 games? 0-1. Here's where it gets stranger: the Cubs' record in those 5 games with dominant pitching performances? 0-5.
Currently, Dempster is 0-2 (fooling some into thinking he is having a bad year), but his underlying stats and 2.28 ERA are more worthy of an All-Star than a pitcher searching for his first win. On the flipside, Yankees' starter Ivan Nova is 4-2, fooling some into believing he is pitching well, but his ERA is 5.69, his WHIP is a scary 1.65 (65 hits in 49 IP!!), and it's no secret that having Jeter, ARod, Teixeira, Swisher, and others for offensive support is a major boost to a pitcher's chances at a victory. Nova helps himself by striking out a lot of batters, but allowing well over one-and-a-half baserunners per inning is no formula for long term success.
Speaking of long term success, Matt Cain has amassed over 1,300 innings in his career so far, including five straight seasons of over 200 innings. Along the way, Cain has been dominant, taking advantage of San Francisco's pitching friendly ballpark en route to a 3.33 career ERA, a WHIP of 1.18, and a K/BB ratio of 2.33. Yet, Matt Cain has a LOSING record of 72-75.
Even after adjusting for ballpark factors, Cain's numbers are eerily similar to Justin Verlander, the reigning AL Cy Young winner (and MVP). BayCityBall.com has all the details, but both pitchers started in 2005, and with very similar career stats, Verlander is 112-58 - a monumental improvement on Cain's winning percentage. Several more years of the same, and Verlander will be making a Hall of Fame speech some day while Cain will have to rely on his peers to relay how good he really was despite a losing record.
These are extreme examples, but the point is made that W-L record means very little in the short term for a pitcher, and in the case of Matt Cain, it doesn't reflect his career success at all. I put a little stock in the guy who can throw a lot of pitches and battle out a 6-5 win because he was durable enough to stick it out and finish the game for the win, but Cain's innings pitched prove his durability, and getting removed for a pinch hitter because of no run support is all beyond Cain's control, so it appears that Cain just happens to be one of the most unlucky pitchers in baseball.
At least a few more of you are now informed of Cain's relative success and know how to spot a good pitcher in spite of wins and losses. If you happen to be in Cooperstown when Verlander is accepting his award someday, please tell the guy next to you about the hardluck pitcher from the Giants.