With the Braves going through a bit of a rough patch of late, I think now is a good time to take a step back and appreciate some of the little things that the Braves are doing right this year.
First up: Chipper Jones. We all have marveled at his ability to discriminate between balls in the strike zone and those outside of it. This is nothing new from Chipper, of course, and you can make the argument that his batting eye is not what it once was (compare his walk and strikeout rates to his career numbers). Still, while he may have lost a bit with age, Chipper retains one of the best batting eyes in the game.
How do we measure this? One way is to look at the percentage of pitches that a player swings at both within the strike zone and out of it. These numbers can be found in FanGraphs' plate discipline statistics; they are "Z-Swing%" and "O-Swing%," respectively. Generally, you want a player to swing very rarely at pitches outside the zone (i.e., balls) and very often at pitches in the zone (i.e., strikes). The hitters with the best "eyes" will have a huge gap between these numbers.
For instance, Chipper this year has swung at 70.5% of pitches in the zone. The league average is around 65%. On the other hand, Chipper has swung at only 22.0% of the pitches outside of the zone, with a league average of around 30%. That's quite a combination: swinging more than average at strikes and less than average at balls.
If you subtract each player's O-Zone% from his Z-Zone%, you can see how much more often that player swings at strikes than at balls. Chipper swings 70.5% of the time at strikes and 22.0% of the time at balls, so his differential is 48.5%. As it turns out, that is the third-highest differential in all of baseball. Here are the top 5 batting eyes by this measure:
- Carlos Peña, 50.8% difference (swings 75.2% at strikes and 24.4% at balls)
- Lance Berkman, 49.9% difference (73.3% at strikes, 23.4% at balls)
- Chipper Jones, 48.5% difference
- Mark Reynolds, 48.4% difference (71.6% at strikes, 23.2% at balls)
- Matt Joyce, 47.1% difference (72.9% at strikes, 25.8% at balls)
The crazy thing is that Chipper's 48.5% difference is low by his career standards. Since 2002, when these stats began being tracked, his career low is 50.0% in 2008. He's actually been above 60% in several years, including a phenomenal 64.6% differential in 2004 (73.7% swings at strikes and only 9.1% swings at balls). I think we can say that Chipper's batting eye isn't quite as good as it was at its peak, but even then, it is still one of the best in baseball.