Thoughts on MLB's New ABS System

[saevel25]

I find this new ABS system interesting on its potential impact on the game of baseball from the pitching perspective. 

The ABS system is projecting a 2D plane at the middle of the plate, instead of having the strike zone be a 3D box (really the dimension of the plate, but no pitcher is nicking that back triangle of the plate). 

MLB to test automated ball-strike challenge system during spring games

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Umpires first began calling both balls and strikes way back in 1864, and baseballers have been arguing about those calls ever since. Strike-zone judgment has been the subject of some untold number of verbal (and, yes...

I was thinking, this should have a big impact on pitchers who throw breaking balls. The breaking ball now has to be thrown higher up in the strike zone to catch the bottom of the new 2D zone. If the 2D zone is about the correct dimension of the previous strike zone, that 2D zone would be at the front of the plate. Now it is 8.5" back. So, the same breaking ball has to be thrown much higher to hit the new position of that low part of the plate. If the ball curves dramatically towards the end of the pitch, where the hitter has to hit the curveball (typically 8 inches in front of the plate), then the curve ball is maybe like 6 inches higher than normal? Just throwing out a number. I think that turns what use to be an at the knee strike into a something a hitter would crush. 

Maybe the opposite is true, that breaking balls at the top of the zone might be more in play. It might look more that the ball is at the shoulders and hit the top of the plate. Maybe pitches who can delay the vertical break of the ball till much later might still see the same success since that delay allows them to keep the ball lower. I still think it will elevate any breaking ball pitch thrown low to clip that bottom of the strike zone. 

 

[iacas]

7 hours ago, saevel25 said:

The ABS system is projecting a 2D plane at the middle of the plate, instead of having the strike zone be a 3D box (really the dimension of the plate, but no pitcher is nicking that back triangle of the plate).

Yes, I've wondered the same thing about breaking pitches, whether they're sinking or whether they're curving horizontally. If you consider that the plate is a rectangular prism (ignoring the back triangle), a ball could break in over the back corner or clip the front corner before continuing to curve farther away from the strike zone. Both pitches could miss the middle of the plate "planar" (2D) rectangle.

7 hours ago, saevel25 said:

If the ball curves dramatically towards the end of the pitch, where the hitter has to hit the curveball (typically 8 inches in front of the plate), then the curve ball is maybe like 6 inches higher than normal?

I don't think it's anywhere near 6". A ball would have to be moving at a 35° angle to drop 6" over 8.5". That feels like an awfully steep angle. A quick search says a breaking ball moves only 6-12" vertically, and I'm not even sure if that's including the normal drop from gravity.

Then of course I remembered this:

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Statcast Pitch Movement Leaderboard | baseballsavant.com

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Baseball Savant

6" over 8.5" would be a TON. Basically unheard of. Unless it's an eephus pitch. 😉 

7 hours ago, saevel25 said:

Maybe the opposite is true, that breaking balls at the top of the zone might be more in play.

No, either way, it shrinks the zone. Whether a ball clips the front of the plate before falling out, or clips the back top of the plate as it drops… it's gonna miss the middle plane of the plate.

ABS has given us things like this, though, which are great:

[saevel25]

11 minutes ago, iacas said:

ABS has given us things like this, though, which are great:

I saw that. That was awesome.