Pirates Bad at Defense, Piracy

For no reason at all: Pitchers with the highest batting averages against on balls in play — that is, batting average against, minus home runs and strikeouts — over the past five years (minimum 600 IP):

Rk Player BAbip IP G GS W L ERA ERA+
1 Zach Duke .330 879.2 146 145 37 68 4.80 88
2 Paul Maholm .321 940.0 153 153 44 58 4.58 93
3 Ian Snell .321 749.2 134 130 37 50 4.74 91
4 Kevin Millwood .320 945.2 156 156 52 62 4.67 96
5 Andy Pettitte .320 957.1 158 155 68 47 4.11 107
6 Doug Davis .318 783.2 135 135 40 49 4.56 101
7 Aaron Harang .318 924.1 148 144 50 55 4.23 106
8 Livan Hernandez .318 995.2 162 162 56 59 4.94 88
9 Kyle Lohse .317 729.0 142 124 39 46 4.86 89
10 Carlos Silva .317 679.0 126 119 39 53 5.37 81
11 Jeff Suppan .316 837.1 157 142 44 49 4.76 89
12 Kyle Davies .314 619.0 117 117 35 50 5.57 78
13 Mike Pelfrey .314 683.0 116 113 43 41 4.31 96
14 Brad Penny .312 720.2 125 122 52 35 4.26 104
15 Nate Robertson .312 706.0 143 114 37 48 5.09 89
Provided by Baseball-Reference.com: View Play Index Tool Used
Generated 12/10/2010.

Just four of the fifteen pitchers have an ERA+ better than 100.

As is sometimes misstated, a lot of a pitcher’s batting average on balls in play is luck and defense, but some is his own skill. Johan Santana’s batting averages against on balls in play — .278 BAbip for his career — are routinely lower than his team’s defense would imply. Mike Pelfrey’s BAbip are routinely higher (.314 career), and thus he is #13 on this list. There’s A LOT of randomness at work, but it’s not ENTIRELY randomness. Johan Santana is actually better at preventing hits on balls in play than Mike Pelfrey. You can see that the list above is populated with the sort of pitchers you might imagine get hit pretty hard, and I don’t think that’s just a function of chance.

That said, as this chart shows, a lot of BAbip is a pitcher’s defensive help. Good defenses will turn more balls into outs than bad defenses, and bad defenses will turn more outs into hits than good ones. The Pirates have been a bad defensive club for five years. The top three pitchers on that list have spent a lot of time pitching for those Pirates. This is probably not a coincidence.

2 Comments

Filed under Statistics, Words

2 responses to “Pirates Bad at Defense, Piracy

  1. Some pitchers throw pitches that get crushed. Some don’t. Those who drink down BABIP and talk about it like there is a ton of luck involved are drinking the BABIP kool-aid. Some hitters crush pitches and run fast. I would imagine that would bolster BABIP a bit more than luck on a few Texas Leaguers.

    • Patrick Flood

      Short term, such as in a single season, luck plays a bigger part in BAbip. That said, luck starts to wash out as you move towards bigger and bigger numbers of innings. And if you play for the Pirates, you’re screwed.

Leave a comment