The decline of the curveball

[JoeC]

On 7/19/2025 at 10:06 PM, Jake said:

I'm not too sure what drove Santiago to change the way he described that pitch. But a lot of guys throwing changeups nowadays are essentially throwing screwballs. Hector gripped it like a circle changeup and threw it like one. I find that in youth ball, it isn't often taught the screwball way so a lot of fans don't realize this. But the best changeups are thrown with total wrist pronation, basically like you'd throw a curveball but with your hand facing the opposite direction (and usually gripped differently). This generates side/overspin, but of course due to the fact it's generally harder to pronate than supinate, it comes out harder and with less overspin than a curveball. Some guys can't really do it at all but they tend to have an easier time throwing sliders. Other guys who are natural at spinning the screwgie changeups often can't throw a slider very well. The "changeup" Devin Williams throws is very much an all-time great screwball.

As for why fewer curveballs, I think the biggest thing is that "tunneling" is the prevailing theory about pitch mixing nowadays. You want all your pitches to look the same not only during your throwing motion but as long as possible after release too. The idea is that they are all traveling down a common "tunnel" towards home plate until at some late stage they diverge due to different movements. The classic tunneling trio is the four-seam/sinker/cutter. These are all very similar out of hand but the cutter darts gloveside late, the sinker darts armside late, and the four seamer stays a bit straighter and will feel like it's rising relative to the other two. Sliders don't tunnel quite as well but the extra movement is a good tradeoff for a lot of pitchers. Same for changeups which diverge a little earlier (mostly due to the speed difference). Curveballs generally don't tunnel very well because the ball comes up out of the hand, making it look different from the heater and everything else almost immediately to a discerning hitter. 

One thing I haven't heard an explanation for yet is why it seems en vogue nowadays to attack opposite-handed hitters with curveballs — and not so much with sliders. As best as I can tell, for a long time there has been a reverse platoon split for curveballs (same-handed batters hit them better than oppo-handed batters which goes against conventional wisdom). But this is mostly isolated to early in the count and when the curveball is thrown outside to the oppo-handed hitters. So basically, especially early in counts oppo-handed batters have a hard time judging the backdoor curveball and take it for strikes. Later in counts, they are more aggressive and don't take those pitches and don't whiff on them either. Same-handed hitters have an easier time judging curveballs because they can't be back-doored and the break is so big and slow they have a chance to measure it in a way that is unlike the slider. 

I will preface this post by saying that I am in no position to disagree with anything you’ve said above.

For curveballs, would tunneling matter all that much? Meaning, if the pitch looks that vastly different out of the hand, does it force the hitter to essentially have to completely adjust their estimated trajectory and timing? Or is there an alternative pitch tunneling combination? I’m thinking of Gio’s short-lived-patented “high change.”

[Jake]

On 7/22/2025 at 1:00 PM, JoeC said:

I will preface this post by saying that I am in no position to disagree with anything you’ve said above.

For curveballs, would tunneling matter all that much? Meaning, if the pitch looks that vastly different out of the hand, does it force the hitter to essentially have to completely adjust their estimated trajectory and timing? Or is there an alternative pitch tunneling combination? I’m thinking of Gio’s short-lived-patented “high change.”

Well I think the prevailing wisdom is that tunneling matters with the curveball insofar as it doesn't tunnel, therefore the hitter immediately recognizes it is a curveball and can turn their attention to figuring out the timing and movement (which might still be difficult if it's a good curveball). I have heard a few mentions of guys who feel like the high fastball and curveball can be a tunneled pairing — if the batter isn't reading the curveball right out of the hand, then he will initially see it as a high heater. You can increase that confusion by actually throwing high heaters to make the hitter respect that possibility. In youth baseball you'll see hitters running out of the batters box on curveballs that end up in the strike zone because the batter thought it was a fastball coming at his earhole. Same principle here, it's just that the hitters are a lot more discerning. FWIW, I've seen it claimed that knuckle curves are not so easily read out of the hand, but I'm not sure whether it's true or why exactly that would be the case.

Giolito's high change approach was a good use of tunneling; his fastball didn't play well at the bottom of the zone so he never threw it there. So if he's throwing a changeup, which is meant to look like his fastball out of the hand, a batter may eventually realize if there's a fastball-looking pitch headed to the bottom of the zone it must be a changeup. Or in other words, he tunneled the changeup and fastball by throwing the changeup higher to keep it in the tunnel with the heater. By keeping them on the same path towards home, it takes the hitter a long time to decide whether the incoming pitch is a fastball or changeup and increases the likelihood that the hitter mis-times his swing or swings at the wrong spot since eventually the changeup probably goes a bit lower than a fastball would. 

Another tidbit for tunneling with high four seamers...I read a while back about teams trying to counter the increased use and optimization of the "rising" four seamer thrown at the top of the zone. Teams were starting to use those fancy pitching machines like the Sox have (can't remember the brand name) to get batting practice against high-rise four seamers thrown at the top of the zone. Hitters seemed to say the mental cue they used after some practice was to try to swing above the pitch and that would result in them squaring it up. Once the pitchers started experiencing the hitters squaring up the four seamer, they started mixing in the occasional high *sinker*. The batter sees it and thinks it's a four seamer and prepares to either 1. take the pitch because he assumes it will miss high or 2. swing high because he knows the pitch will ride up relative to how it looks. But when it's a sinker, you either get 1. taken for a strike because it dropped into the zone or 2. Guy swings way above it. 

I remember an at bat earlier this year between Miguel Vargas and Walker Buehler where Buehler sneaks in a sinker to end it.

Strike 1: Four seamer at the top of the zone, Vargas takes because at this point before his swing change he's very weak to that pitch (even from a relative soft-tosser like Buehler).


Strike 2: Another four seamer in the upper portion, he decides to swing but he's underneath it. 


Strike 3: Vargas is probably expecting Buehler to elevate a four seamer out of the zone, knowing that Vargas can't touch it. Buehler may be thinking instead that even though Vargas can't hit a fastball, he's got a great batting eye and probably won't chase up out of the zone here. So let's throw him a sinker which will look like a four seamer up and out of the zone right up until it drops back in for strike 3. 


The fun of the chess match here is that the high sinker is only going to work if the hitter is totally locked in on a four seamer. If he's a little more cognizant of the sinker or other pitch types, the sinker is a pitch he will find easy to hit by just naturally reacting to it. So Buehler wins this one but the moment a hitter is looking for that pitch he will likely pay a big price.

Similar principle applies to Luis Castillo of the Mariners. He's got one of the nastiest sinkers in baseball, high-velocity and runs a ton towards the inside part of the plate to right-handers. He has a very effective slider...even though that slider has literally zero sideways movement on average. But it's coming out of the same tunnel as that sinker, making batters perceive it almost as if it's breaking a ton towards the glove side. And thanks to Castillo's sinker, there is indeed 20 inches of difference in the horizontal movement of those two pitches even though they will spend much of their trip to home plate looking almost identical. Castillo also has a 4-seamer that doesn't have a ton of ride, but compared to his sinker has an extra 9 inches of carry. Those two playing off of each other will make batters really off balance even though only one of the pitches in his arsenal has truly great movement.

Edited July 23 by Jake

[Lip Man 1]

11 minutes ago, Jake said:

Well I think the prevailing wisdom is that tunneling matters with the curveball insofar as it doesn't tunnel, therefore the hitter immediately recognizes it is a curveball and can turn their attention to figuring out the timing and movement (which might still be difficult if it's a good curveball). I have heard a few mentions of guys who feel like the high fastball and curveball can be a tunneled pairing — if the batter isn't reading the curveball right out of the hand, then he will initially see it as a high heater. You can increase that confusion by actually throwing high heaters to make the hitter respect that possibility. In youth baseball you'll see hitters running out of the batters box on curveballs that end up in the strike zone because the batter thought it was a fastball coming at his earhole. Same principle here, it's just that the hitters are a lot more discerning. FWIW, I've seen it claimed that knuckle curves are not so easily read out of the hand, but I'm not sure whether it's true or why exactly that would be the case.

Giolito's high change approach was a good use of tunneling; his fastball didn't play well at the bottom of the zone so he never threw it there. So if he's throwing a changeup, which is meant to look like his fastball out of the hand, a batter may eventually realize if there's a fastball-looking pitch headed to the bottom of the zone it must be a changeup. Or in other words, he tunneled the changeup and fastball by throwing the changeup higher to keep it in the tunnel with the heater. By keeping them on the same path towards home, it takes the hitter a long time to decide whether the incoming pitch is a fastball or changeup and increases the likelihood that the hitter mis-times his swing or swings at the wrong spot since eventually the changeup probably goes a bit lower than a fastball would. 

Another tidbit for tunneling with high four seamers...I read a while back about teams trying to counter the increased use and optimization of the "rising" four seamer thrown at the top of the zone. Teams were starting to use those fancy pitching machines like the Sox have (can't remember the brand name) to get batting practice against high-rise four seamers thrown at the top of the zone. Hitters seemed to say the mental cue they used after some practice was to try to swing above the pitch and that would result in them squaring it up. Once the pitchers started experiencing the hitters squaring up the four seamer, they started mixing in the occasional high *sinker*. The batter sees it and thinks it's a four seamer and prepares to either 1. take the pitch because he assumes it will miss high or 2. swing high because he knows the pitch will ride up relative to how it looks. But when it's a sinker, you either get 1. taken for a strike because it dropped into the zone or 2. Guy swings way above it. 

I remember an at bat earlier this year between Miguel Vargas and Walker Buehler where Buehler sneaks in a sinker to end it.

Strike 1: Four seamer at the top of the zone, Vargas takes because at this point before his swing change he's very weak to that pitch (even from a relative soft-tosser like Buehler).


Strike 2: Another four seamer in the upper portion, he decides to swing but he's underneath it. 


Strike 3: Vargas is probably expecting Buehler to elevate a four seamer out of the zone, knowing that Vargas can't touch it. Buehler may be thinking instead that even though Vargas can't hit a fastball, he's got a great batting eye and probably won't chase up out of the zone here. So let's throw him a sinker which will look like a four seamer up and out of the zone right up until it drops back in for strike 3. 


The fun of the chess match here is that the high sinker is only going to work if the hitter is totally locked in on a four seamer. If he's a little more cognizant of the sinker or other pitch types, the sinker is a pitch he will find easy to hit by just naturally reacting to it. So Buehler wins this one but the moment a hitter is looking for that pitch he will likely pay a big price.

Similar principle applies to Luis Castillo of the Mariners. He's got one of the nastiest sinkers in baseball, high-velocity and runs a ton towards the inside part of the plate to right-handers. He has a very effective slider...even though that slider has literally zero sideways movement on average. But it's coming out of the same tunnel as that sinker, making batters perceive it almost as if it's breaking a ton towards the glove side. And thanks to Castillo's sinker, there is indeed 20 inches of difference in the horizontal movement of those two pitches even though they will spend much of their trip to home plate looking almost identical. Castillo also has a 4-seamer that doesn't have a ton of ride, but compared to his sinker has an extra 9 inches of carry. Those two playing off of each other will make batters really off balance even though only one of the pitches in his arsenal has truly great movement.

Pitching is not only a science but a big mental chess match. 

[Jake]

12 minutes ago, Lip Man 1 said:

Pitching is not only a science but a big mental chess match. 

I love how it can simultaneously be that while sometimes being "Chris Sale throws 100 sidearm and I have no clue how to hit it" or (IIRC) guys like Albert Belle who didn't want instruction on their swings, etc. and pretty much just liked to pound a few cups of coffee and mash.

I'm sympathetic to the "keep it simple" hitters. Once I was finished with high school ball, I became a pitcher-only as I tried to play small-time college ball. I was just okay as a high school hitter but tended to overthink. In the travel circuit and college summer league circuit, I had a handful of situations where I had to be an emergency pinch hitter due to injuries — I would have gone at least weeks without batting practice or in-game at bats in these cases. I batted literally 1.000 in those situations and there's no doubt in my mind that besides a little luck, it was all because my mind wasn't cluttered with swing thoughts, attempted adjustments from previous at bats, all that junk. You might say that half the chess match is against yourself.

[JoeC]

2 hours ago, Jake said:

Well I think the prevailing wisdom is that tunneling matters with the curveball insofar as it doesn't tunnel, therefore the hitter immediately recognizes it is a curveball and can turn their attention to figuring out the timing and movement (which might still be difficult if it's a good curveball). I have heard a few mentions of guys who feel like the high fastball and curveball can be a tunneled pairing — if the batter isn't reading the curveball right out of the hand, then he will initially see it as a high heater. You can increase that confusion by actually throwing high heaters to make the hitter respect that possibility. In youth baseball you'll see hitters running out of the batters box on curveballs that end up in the strike zone because the batter thought it was a fastball coming at his earhole. Same principle here, it's just that the hitters are a lot more discerning. FWIW, I've seen it claimed that knuckle curves are not so easily read out of the hand, but I'm not sure whether it's true or why exactly that would be the case.

Giolito's high change approach was a good use of tunneling; his fastball didn't play well at the bottom of the zone so he never threw it there. So if he's throwing a changeup, which is meant to look like his fastball out of the hand, a batter may eventually realize if there's a fastball-looking pitch headed to the bottom of the zone it must be a changeup. Or in other words, he tunneled the changeup and fastball by throwing the changeup higher to keep it in the tunnel with the heater. By keeping them on the same path towards home, it takes the hitter a long time to decide whether the incoming pitch is a fastball or changeup and increases the likelihood that the hitter mis-times his swing or swings at the wrong spot since eventually the changeup probably goes a bit lower than a fastball would. 

Another tidbit for tunneling with high four seamers...I read a while back about teams trying to counter the increased use and optimization of the "rising" four seamer thrown at the top of the zone. Teams were starting to use those fancy pitching machines like the Sox have (can't remember the brand name) to get batting practice against high-rise four seamers thrown at the top of the zone. Hitters seemed to say the mental cue they used after some practice was to try to swing above the pitch and that would result in them squaring it up. Once the pitchers started experiencing the hitters squaring up the four seamer, they started mixing in the occasional high *sinker*. The batter sees it and thinks it's a four seamer and prepares to either 1. take the pitch because he assumes it will miss high or 2. swing high because he knows the pitch will ride up relative to how it looks. But when it's a sinker, you either get 1. taken for a strike because it dropped into the zone or 2. Guy swings way above it. 

I remember an at bat earlier this year between Miguel Vargas and Walker Buehler where Buehler sneaks in a sinker to end it.

Strike 1: Four seamer at the top of the zone, Vargas takes because at this point before his swing change he's very weak to that pitch (even from a relative soft-tosser like Buehler).


Strike 2: Another four seamer in the upper portion, he decides to swing but he's underneath it. 


Strike 3: Vargas is probably expecting Buehler to elevate a four seamer out of the zone, knowing that Vargas can't touch it. Buehler may be thinking instead that even though Vargas can't hit a fastball, he's got a great batting eye and probably won't chase up out of the zone here. So let's throw him a sinker which will look like a four seamer up and out of the zone right up until it drops back in for strike 3. 


The fun of the chess match here is that the high sinker is only going to work if the hitter is totally locked in on a four seamer. If he's a little more cognizant of the sinker or other pitch types, the sinker is a pitch he will find easy to hit by just naturally reacting to it. So Buehler wins this one but the moment a hitter is looking for that pitch he will likely pay a big price.

Similar principle applies to Luis Castillo of the Mariners. He's got one of the nastiest sinkers in baseball, high-velocity and runs a ton towards the inside part of the plate to right-handers. He has a very effective slider...even though that slider has literally zero sideways movement on average. But it's coming out of the same tunnel as that sinker, making batters perceive it almost as if it's breaking a ton towards the glove side. And thanks to Castillo's sinker, there is indeed 20 inches of difference in the horizontal movement of those two pitches even though they will spend much of their trip to home plate looking almost identical. Castillo also has a 4-seamer that doesn't have a ton of ride, but compared to his sinker has an extra 9 inches of carry. Those two playing off of each other will make batters really off balance even though only one of the pitches in his arsenal has truly great movement.

Thank you for this post and giving me more insight into the art of pitching.

This right here, as an engineer and former athlete, is why I'm falling more and more in love with baseball as I age, in spite of the Sox's best efforts.