David Price and the de facto Strike Zone

The Boston Red Sox new ace had a rough first month, but seemed to straighten it out in his last start. During the last at-bat of his start against the Atlanta Braves, the left-hander got the batter out on a questionable called strike three. After taking a closer look, Damian Dydyn examines David Price and the de facto strike zone.

On April 27, David Price began his night in a way that was starting to become soul-crushingly familiar: He struggled a bit early and many fans braced themselves for another poor start. However, as the game went on, he grew more effective and eventually capped off his night by tying his career-high in strikeouts at fourteen. His final punch out was on a called strike that, on the on-screen strike zone indicator, appeared to be well inside to hitter Tyler Flowers in the 8th inning. Here is the at-bat, as shown by Brooks Baseball:

The last pitch is that red square (labelled “5”) to the left of the black rectangle that represents the strike zone. This view is from the catcher’s perspective, so Flowers would be on the left side of the plot. The umpire (Joe West) clearly missed it, right?

Here are the same pitches, this time mapped onto the de facto strike zone, as defined by Ian York:

This plot is of Price’s entire 8th inning, not just the Flowers at bat, and the hollow blue dot just on the edge of the zone is the called third strike against Flowers. Doesn’t look quite so bad now, does it? It actually overlays the edge of the de facto strike zone, meaning that at least 50% of the time, umpires will call that pitch a strike. Certainly it was far too close to let go on a third strike. The de facto strike zone is what an umpire calls consistently, which is far more important than the zone as defined by the rulebook which telecasts try to approximate with an even lined rectangle on the screen:

Many argue that umpires should call the zone as it is defined in the rulebook, and in a perfect world perhaps they would. However, the rectangle you see here isn’t actually the rulebook strike zone. As defined, the strike zone will vary from hitter to hitter. That rectangle is actually an approximation of many strike zones, meaning there is a margin for error that can measure up to an inch or more, depending on who is at the plate.

This means that any strike zone displayed as a smooth rectangle has to be taken with a grain of salt. The actual strike zone that umpires have to call isn’t static and on average, they actually do a very good job of calling balls and strikes.

Joe West called a strike that he had been calling consistently throughout the night. In fact, there were several pitches that were actually outside of his normal zone that were still called strikes which may or may not have had something to do with catcher Christian Vazquez’s pitch framing skills:

It is on the hitter to adjust to the strike zone being called. West’s zone was consistent and Flowers shouldn’t have let that pitch pass. Luckily for Sox fans, he did and Price capped off an impressive night in spectacular fashion.

Damian Dydyn has written about an illegal slide, Mookie Betts, rookies adjusting, and managing a fantasy baseball team.

Follow Damian on Twitter @ddydyn.

About Damian Dydyn 40 Articles
Damian grew up smack dab in the middle of Connecticut and was indoctrinated into the culture of Red Sox fandom from the moment he was old enough to start swinging a bat. A number of trips to Fenway park and meeting Ellis Burks at his dad's bar cemented what would become a life long obsession that would pay off in spades in both the recent run of post season success and the extra bit of connection he would have with his father throughout the years. After a brief three year stint living in the Bronx with his wife where he enjoyed leisurely strolls through the neighborhood with a Red Sox t-shirt on to provoke the natives, he settled in Roanoke, Virginia where he can fall out of bed and land at a Salem Red Sox game. Damian is a co-host for Sports & Sorts Shorts with Shane Moore, a baseball podcast covering Red Sox and Yankees topics.

Be the first to comment

Leave a Reply

Your email address will not be published.