What a Smaller Strike Zone Can Do for Pace of Play
Last week, I discussed the consequences of an expanded strike zone on the game, finding that it leads to more strikeouts and fewer balls in play. While some have suggested that a larger zone — by inviting more swings from batters — might actually result in an uptick in batted balls, the observed results don’t support that hypothesis. Whatever gains a larger zone creates in terms of swing rate, they’re negated by an increase both in whiff rate and called strikes, leading to more strikeouts overall.
What that post addressed was what would happen if the strike zone got bigger. This post attempts to answer a similar question — namely, what would happen if the strike zone got smaller?
In order to test the effects of a shrinking strike zone, it’s necessary first to identify an actual instance in which the strike zone has gotten smaller. Fortunately, such an instance exists, thanks again to the research of Jon Roegele, who produced this visual in his piece on the strike zone last year.
That’s the 2007 strike zone on the left and 2017 zone on the right. As you can see, the outside edge to lefties used to be called a lot more frequently than it is now. The bottom of the zone has gotten larger for both lefties and righties (a point addressed in my last post), and the result has been a smaller strike zone for lefties than their right-handed counterparts.
The bottom of the strike zone is falling again this season!
The overall size of the strike zone is the same as last year, but the low part of the zone has expanded again after having contracted each of the past two seasons. Average pitch height crossing home plate is lower, too. pic.twitter.com/pkAg3gIP1R
— Jon Roegele (@MLBPlayerAnalys) May 30, 2018