Comparing strike zones for Sabathia and Verlander

During last night's ALDS Game Three between the New York Yankees and Detroit Tigers, Yankee manager Joe Girardi mentioned during his in-game interview that he thought CC Sabathia wasn't getting some borderline calls from home plate umpire Gerry Davis.  He also brought it up in the post-game interview saying of CC, “I actually thought he made a lot of good pitches tonight and I thought the zone was a small zone.”

So was CC getting squeezed? Was Justin Verlander getting a better strike zone to work with?  Or both?

Let’s take a look at some of the numbers and heat maps.

(Click image to enlarge)

The most noticeable difference here is the strikes Gerry Davis was calling for Verlander off the outside edge to lefty hitters.  Verlander also benefitted from a few strikes that were a bit high.  However, it's tough to say whether CC would have gotten any similar calls in that area since he didn't throw anything there that was taken by any Detroit hitters. The up and away strike to RHB also seems to have tipped in Verlander's favor, while CC was getting the low and away area.

So what do the numbers say?

Game 3 - Gerry Davis Strike Zone

	Strike Zone Called Balls	Out of Strike Zone Called Strikes
Sabathia	6	3
Verlander	5	10

	Called Strike% In Strike Zone	Called Strike% Out of Strike Zone
Sabathia	62.5%	7.3%
Verlander	70.6%	19.6%

So what does this tell us? Essentially, CC and Verlander missed out on about the same number of called strikes in the strike zone. However, Verlander greatly benefited from an expanded zone, getting more than three times as many called strikes on pitches outside of the PitchFX defined strike zone. Most of those pitches are likely the outside strikes to lefties you see in the above heat maps.

As for the percentages, CC was getting fewer strikes called overall in the strike zone. A 62.5% strike zone called strike rate is pretty low. During the regular season, Gerry Davis correctly called 76.8% of strikes in the strike zone, and 78.9% for left-handed pitchers. For whatever reason, he simply was not giving CC much of a zone to work with yesterday.

Granted, we are talking about a total of just 16 taken pitches in the strike zone for CC and 17 for Verlander. If CC was throwing to some borderline spots that Gerry Davis does not normally call while Verlander was not, it could explain the disproportionate results.

However, for strikes called out of the strike zone, it is pretty clear that Verlander was the big beneficiary in last night's game. Three of his strikes called on pitches out of the zone were deciding strike three pitches.

Comparing Sabathia Seasons

CC Sabathia of the New York Yankees finished his regular season work this week.  He'll pitch a simulated game before his start in the playoffs.  His 2011 ended 1/3 of an inning short of his 2010 total, making a comparison of the two seasons easy.  CC pitched both better and worse than last year.

The big lefty posted a 3.00 ERA, 0.18 runs lower than in 2010.  His opposition batting statistics, however, were a bit higher.

	2010	2011
Avg	0.239	0.255
OBP	0.301	0.305
Slug	0.355	0.361
wOBA	0.291	0.294

Note that what happened was an increase in singles allowed.  He walked fewer batters (only a four point increase in his OBP) and gave up fewer long hits (a six point increase in slugging percentage).  CC traded some walks for singles, and as far as his ERA was concerned, it didn't matter that much.

The real improvement in Sabathia shows up in his attacking the strike zone:

	2010	2011
Strike %	63.3%	66.4%
Swing %	45.9%	47.9%
Miss %	22.0%	24.9%
Chase %	30.2%	32.4%
Called Strike%	32.2%	35.6%

Milliliter not only induced more swings, he induced batters to chase more pitches out of the zone, resulting in more misses.  On top of that, CC picked up more strikes when batters didn't swing.  He did a better job dominating the strike zone, so why did he give up more hits?

	2010	2011
In Play Pct	42.0%	39.8%
BABIP	0.283	0.322

Even though hitters were putting the ball in play less, they were finding holes more.  Let's face it, the Yankees left side of the infield is getting old, and more balls get through on that side of the field.  With better defense behind him CC might have dropped his ERA even further.  His increased strikeout rate and lower walk rate made up for the fielders behind him.

Sabathia's Boston Problem

CC Sabathia of the New York Yankees pitched very well this season, except against the Boston Red Sox.  CC's problems occur on three of his four pitches; the fastball, the sinker, and the change up.  His problems are two-fold, in that his pitches miss the strike zone more, and the Boston hitters track his offerings better.

Overall, Sabathia does an excellent job of hitting the strike zone with those three pitches:

CC Sabathia, pitch frequency, fastballs, sinkers, change ups, 2011.He misses to the catcher's right hand, and close enough that batters will often go after those pitches.  Against the Red Sox, he misses wider:

CC Sabathia, pitch frequency vs. Boston, fastballs, sinkers, change ups, 2011.CC also avoids the middle of the plate more, especially up.  The following table shows how these wide misses hurt Sabathia:

Fastball, Sinker, Change Up 2011	All Teams	Red Sox
In Strike Zone %	51.2	44.7
Strike %	67.5	61.8
Called Strikes %	35.2	29.7
Swing %	49.9	45.7
Miss % (of swings)	18.8	15.0
Chase %	31.4	27.0

The first three rows represent CC's break down.  He throws fewer pitches in the zone, and that leads to fewer strikes, mostly because there are fewer pitches to take for strikes.  The next three rows show how the Red Sox react to this.  A team of selective hitters, they swing less, especially since fewer pitches are in the strike zone.  Swinging at better pitches, (lower chase %) they make more contact (fewer misses).  That leads to this statistical disparity for Sabathia:

Fastball, Sinker, Change Up 2011	All Teams	Red Sox
Batting Average	0.262	0.357
On Base Percentage	0.323	0.373
Slugging Percentage	0.361	0.561
wOBA	0.303	0.417

Even a great pitcher can't afford to make too many mistakes against the Red Sox.