The Athletic: MLB just tweaked Triple A’s electronic strike zone: What you need to know and why it matters

Let’s try to clear this up:

The “old” zone: Hopefully, you recall the piece we published last month, looking at what’s gone on while MLB was spending this season trying out electronic ball-strike technology (aka “ABS” for Automated Ball-Strike System) across Triple A for the first time. As part of that experiment, the league also lowered the top of the strike zone by about two inches. So has that lower zone been a popular change? Ha. Let’s just say it’s been a zesty topic of nonstop chatter among hitters and pitchers in those leagues. Imagine that.

The “new” zone: The magic word to describe what’s changing isn’t “bigger” or “smaller.” It’s more like “personalized.” The league is now empowering its all-powerful Hawk-Eye technology to make every hitter’s electronic zone more individualized. Sounds simple, right? Not that simple, actually.

Before this, every hitter who was, say, 6-foot-3, was assigned exactly the same zone by the robot umps. But perhaps you’ve noticed that not every 6-foot-3 human has the same build. All those 6-foot-3 baseball-playing humans certainly did. So thanks to Hawk-Eye, now they won’t all have the same strike zone anymore.

For the rest of this season, the top of each hitter’s zone will be a spot defined as “two baseballs above the midpoint of his hip” — which works out to approximately one baseball’s width higher than his belt. The technology makes it possible to determine precisely where that is, no matter who’s hitting. That wasn’t true in the early days of the robot ump era.