Javier Vazquez and the Strike Zone

Javier Vazquez entered the 6th inning against the Tampa Bay Rays last night by walking Ben Zobrist. What ensued afterward was horrific for Yankee fans to watch, as he proceeded to hit not one, not two, but three consecutive batters, including Desmond Jennings and Willy Aybar on consecutive pitches. Here are the characteristics of the three HBPs:

1. 67 MPH curveball to RHH
2. 91 MPH fastball to RHH
3. 73 MPH curveball to RHH

It’s just been that kind of year for Vazquez. His K/9 is down from 9.77 last year to 7.10 this year. More concerning is his current 3.67 BB/9, a career high. He has also more than doubled his home runs allowed rate and increased his FIP from 2.77 last season (.297 BABIP) to 5.34 this season (.274 BABIP). Looking at plate discipline statistics, Vazquez has a career low in Zone% this season with 45.0% (compared to 49.4% from last season). Batters are also getting more contact this season when they swing (Contact% of 81.2%) compared to last season (73.3%). Both first pitch strikes and swinging strikes are down significantly.

A look at the density plots of each of Vazquez’s pitches may tell us which pitch Vazquez has lost control of this season. Vazquez throws a fastball, slider, curveball, and changeup. Let’s take a look at Vazquez’s fastballs against both RHH and LHH in 2009 and 2010:

The red points represent fastballs from all right-handed pitchers that hit the batter that season to give an idea of where the batter stands. It appears that Vazquez is throwing many more fastballs outside of the zone this season compared to last. Both fastballs to RHH and LHH are outside the zone more often in 2010. Let’s look at Vazquez’s sliders:

Against RHH, Vazquez is throwing a lot more low and away sliders, some of them presumably in the dirt. Against LHH, Vazquez is throwing a lot more inside sliders this season than last season, coming dangerously close to hitting left-handed hitters. Let’s look at Vazquez’s curveballs:

At first glance, it looks like Vazquez is hitting the strikezone more when throwing curveballs to RHH, as well as avoiding curveballs that land a foot below the strikezone. There do seem to be more high, hanging curveballs than before against both RHH and LHH. Finally, let’s look at Vazquez’s changeups:

Vazquez is hitting the strikezone more with changeups against RHH and seems to be throwing more outside changeups to LHH. A look at Vazquez’s pitch type values shows significant decreases in values for all of his pitches. With the exception of changeups, the run value of all of Vazquez’s pitches have been below average. Still, even if Vazquez is hitting the zone more often with his changeups, his wCH/C decreased from a stellar 2.56 runs above average per 100 changeups down to 0.03 runs this season, suggesting that Vazquez’s decline has more to do than just loss of control.