MiLB Pitcher Spin Rates

Enscheff

Well-known member
There has been a lot of recent discussion about how good a pitcher like Anderson is when his excellent results don't quite match some of the reports we have on things like spin rates and velocity. Since we don't have "real data" on those values, most folks have taken a wait and see approach.

FG's prospect board lists spin rates for pitchers, but only list "FB" and "Break". We don't know if "FB" is a SI or FA (low spin rate on SI is ok, low spin rate on a FA is bad), so it isn't as precise as we'd like it. However, we can check it's accuracy by comparing the value listed on the prospect boards to what statcast says about guys who actually have MLB data.

FG board: https://www.fangraphs.com/prospects/the-board/2019-in-season-prospect-list?sort=-1,1&type=3&team=atl
and: https://www.fangraphs.com/prospects/the-board/2019-prospect-list?sort=-1,1&type=3&team=atl

Statcast data: https://baseballsavant.mlb.com/stat...aunch_speed&sort_order=desc&min_pas=0#results

Guys who appear on both for 2019 (FG vs Real):

Soroka: 2280 vs 2364 on FB, 2725 vs 2750 on breaking
Wright: 2400 vs 2410 on FB, 2600 vs 2678 on breaking
Touki: 2225 vs 2178 on FB, 2700 vs 2469 on breaking (something is wrong with Touki in 2019)
Ynoa: 2350 vs 2287 on FB, 2700 vs 2613 on breaking
Wilson: 2200 vs 2231 on FB, 2450 vs 2299 on breaking
Sobotka: 2425 vs 2509 on FB, 2800 vs 2946 on breaking (this is why he will get infinite chances)

The secondhand values on FG seem to track fairly well with what we see actually measured by MLB statcast systems.

This brings us to Ian Anderson: 2175 RPM on the FB, 1700 RPM on the breaking ball.

The FB spin rate would be worse than everyone other than DK and Fried, both of whom have a known flat FA. If Anderson throws a SI the low spin rate may not be such an issue because a lower spin rate will actually lead to more sink (Soroka's SI spins at 2189 RPM). Do we know what type of heater Anderson throws?

The breaking ball spin rate is much more concerning. That 1700 RPM value is shockingly low. The lowest RPM for any Braves SL is 2206, and the lowest RPM for any Braves CU is 2313. A value of 1700 is sooo bad...like among the worst in all MLB bad. If accurate, I'm not sure how a breaking ball with such low RPM could result in a usable pitch.

So does that mean Anderson is dominating MiLB hitters with velocity and elite extension? Do we expect that to work at the MLB level?

I'm hesitant to doom a SP before he even throws a pitch at the MLB level, but I have a hard time imagining how a SP is going to produce without a viable breaking ball. We have to hope that 1700 value is wrong, and when we get real data on Anderson's breaking ball it ends up being a viable pitch.
 
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There has been a lot of recent discussion about how good a pitcher like Anderson is when his excellent results don't quite match some of the reports we have on things like spin rates and velocity. Since we don't have "real data" on those values, most folks have taken a wait and see approach.

FG's prospect board lists spin rates for pitchers, but only list "FB" and "Break". We don't know if "FB" is a SI or FA (low spin rate on SI is ok, low spin rate on a FA is bad), so it isn't as precise as we'd like it. However, we can check it's accuracy by comparing the value listed on the prospect boards to what statcast says about guys who actually have MLB data.

FG board: https://www.fangraphs.com/prospects/the-board/2019-in-season-prospect-list?sort=-1,1&type=3&team=atl
and: https://www.fangraphs.com/prospects/the-board/2019-prospect-list?sort=-1,1&type=3&team=atl

Statcast data: https://baseballsavant.mlb.com/stat...aunch_speed&sort_order=desc&min_pas=0#results

Guys who appear on both for 2019 (FG vs Real):

Soroka: 2280 vs 2364 on FB, 2725 vs 2750 on breaking
Wright: 2400 vs 2410 on FB, 2600 vs 2678 on breaking
Touki: 2225 vs 2178 on FB, 2700 vs 2469 on breaking (something is wrong with Touki in 2019)
Ynoa: 2350 vs 2287 on FB, 2700 vs 2613 on breaking
Wilson: 2200 vs 2231 on FB, 2450 vs 2299 on breaking
Sobotka: 2425 vs 2509 on FB, 2800 vs 2946 on breaking (this is why he will get infinite chances)

The secondhand values on FG seem to track fairly well with what we see actually measured by MLB statcast systems.

This brings us to Ian Anderson: 2175 RPM on the FB, 1700 RPM on the breaking ball.

The FB spin rate would be worse than everyone other than DK and Fried, both of whom have a known flat FA. If Anderson throws a SI the low spin rate may not be such an issue because a lower spin rate will actually lead to more sink (Soroka's SI spins at 2189 RPM). Do we know what type of heater Anderson throws?

The breaking ball spin rate is much more concerning. That 1700 RPM value is shockingly low. The lowest RPM for any Braves SL is 2206, and the lowest RPM for any Braves CU is 2313. A value of 1700 is sooo bad...like among the worst in all MLB bad. If accurate, I'm not sure how a breaking ball with such low RPM could result in a usable pitch.

So does that mean Anderson is dominating MiLB hitters with velocity and elite extension? Do we expect that to work at the MLB level?

I'm hesitant to doom a SP before he even throws a pitch at the MLB level, but I have a hard time imagining how a SP is going to produce without a viable breaking ball. We have to hope that 1700 value is wrong, and when we get real data on Anderson's breaking ball it ends up being a viable pitch.


We'll never know until we know is how I have resigned myself to it.

Everything I read about his fastball suggests it has strong downward action, but no one seems to describe it as a two seamer.

I suspect he spots his pitches pretty well down and away, erring out of the zone, and that helps explain his BBs and low HR rate. I'm not sure how to explain the Ks if he doesn't have a good breaking ball. I think he sits 92-94, so it's not like AA hitters should be blown away by that to the extent that he leads AA in Ks. That doesn't really make a lot of sense.

Just have to see what he is when he advances. It's a mystery.
 
How much of an outlier is it to have a pitcher with such a significant differential in their fastball spin rate and their breaking ball spin rate in the way that it is for Anderson? The answer to that question could give us a hint about whether or not the spin rate data is off.
 
When I saw Anderson in Rome he definitely was not throwing a sinker. He primarily worked off of a mid 90s fastball up in the zone. I remember one inning where he walked 2 or 3 guys straight, all on high fastballs. He was visibly angry with himself, presumably because he couldn't get the ball down.
 
How much of an outlier is it to have a pitcher with such a significant differential in their fastball spin rate and their breaking ball spin rate in the way that it is for Anderson? The answer to that question could give us a hint about whether or not the spin rate data is off.

Good point. Almost every pitcher I’ve looked at has higher RPM on the breaking ball than the fastball.

Like many others, I have a hard time believing that 1700 value.
 
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From FG chat:


Nick: I’m having trouble putting together Ian Anderson‘s performance on the field with his incredibly poor spin rate on the curveball. Is that spin rate cause for concern in the big leagues that makes him a sell high candidate for Atlanta, or how else is he getting these results with a breaking ball that has such a bad spin rate?




12:07
Eric A Longenhagen: It’s spin efficient. He has an over the top slot so all that tumble is occurring straight down and the pitch has workable movement despite lackluster raw spin. Same for MacKenzie Gore.
 
From FG chat:


Nick: I’m having trouble putting together Ian Anderson‘s performance on the field with his incredibly poor spin rate on the curveball. Is that spin rate cause for concern in the big leagues that makes him a sell high candidate for Atlanta, or how else is he getting these results with a breaking ball that has such a bad spin rate?




12:07
Eric A Longenhagen: It’s spin efficient. He has an over the top slot so all that tumble is occurring straight down and the pitch has workable movement despite lackluster raw spin. Same for MacKenzie Gore.


Does spin rate matter as anything other than a secondary indicator of movement and overall health?
 
It’s not just that 1700 is a bad spin rate...it would be the worst in the league. I have a hard time believing every other pitcher with spin rates in the mid-2000s has such a bad spin axis that they only get similar break as Anderson, and Anderson spins the ball on such a perfect axis he gets acceptable break. Every other team understands spin axis.

We really need to see actual MLB data before we can say anything.
 
I just went down a rabbit hole on spin rate. Transverse spin, gyro spin, Magnus effect, etc.

All told, it's entirely possible for lower spin pitchers to get more movement than a higher spin pitcher if the lower spin pitcher's axis is better. And it would seem an over the top pitcher might get a better spin axis on a curve.

That being said, I'm with Enscheff in that I have a hard time believing that a league worst spin rate curve could be a weapon at the major league level. It might be possible for a curve with that spin to play up to an average offering if the axis is great but I can't see it being an out pitch at the major league level.
 
i just have a hard time believing a newly 21-year old could dominate AA so thoroughly with below average stuff and a league-worst spin rate. i'll have to assume something is wrong along the way.
 
Average MLB spin rate on a curve in 2019 is 2529 RPM.

If Anderson gets average MLB movement with his 1700 RPM curve at 100% spin efficiency, then that means the average MLB curve at 2529 RPM is only spun on an axis with ~67% spin efficiency (assuming magnus force is linearly proportional to effective spin rate). That suggests Anderson is the only pitcher in the game who spins the ball on the proper axis, and no other team understands spin efficiency well enough to instruct their pitchers.

Very hard to believe.

There are 2 likely possibilities:

1. The 1700 RPM value is wrong, and Anderson actually has a good breaking ball.
2. The 1700 RPM value is right, and Anderson is beating impatient AA hitters with effective velocity and erratic control.

We will know the answer for sure the day after he makes his MLB debut.
 
i just have a hard time believing a newly 21-year old could dominate AA so thoroughly with below average stuff and a league-worst spin rate. i'll have to assume something is wrong along the way.

It's very strange. There are a couple explanations but none of them is really satisfying.

First, it could be his fastball is so overpowering that makes up for underdeveloped secondary offerings. However, while reports of Anderson's fastball are good, they hardly cast it as so elite as to explain his dominance by him simply blowing the ball past hitters.

The next could be that Anderson's changeup has improved to the point that it's a plus-plus pitch. While I've read (from MLB Pipeline I think) that his change has passed his curve at this point, I don't see anyone saying he has a Trevor Hoffman change.

Next, it could be his just more advanced than the hitters and is taking advantage of the poor plate discipline of minor leaguers. If he was living outside the zone and relying on minor leaguers to chase, that would explain the walk issues in his career. But it seems like that would be something that even minor leaguers would figure out. It would seem he'd get less effective the longer he stayed at a level instead of more effective as we've seen.

It could also be that the spin rate numbers are wrong. Maybe they're based off of one outing where Anderson was sick or nursing a blister. If the sample size isn't large enough, the low spin rate number being reported could have been an outlier. I think this is the most likely explanation. While it would require someone being somewhat sloppy in their reporting, it's the only explanation I see that makes the facts jive with the results.
 
Just seems odd that Anderson's managing of really mediocre or worse tools in a fairly high level of minor league ball would result in stats that are league best or near to it.

That seems almost as unlikely as he has the best spin axis in the world. Well probably not AS unlikely.
 
I can't wrap my mind around a pitcher having a significantly worse spin rate on the curve than the fastball. Just doesn't seem to make sense.

I think the most likely explanation is that Anderson has below-average spin rate (though not nearly as low as reported on the curve) but with his velocity and spin axis, he has 3 quality pitches (fastball, curve, and change) and is a fairly advanced pitcher for his age. That would probably put him potentially at about a 3 and possibly a 2 if he gets his command....under control.
 
Spin wouldn't effect the perceived extension he gets right?

I know there was some chatter about him getting otherworldly extension and it being a weapon, but I can't make the two affect one another.
 
Spin wouldn't effect the perceived extension he gets right?

I know there was some chatter about him getting otherworldly extension and it being a weapon, but I can't make the two affect one another.

Extension is just how far out towards the plate he releases the ball, so the ball is literally in the air for a shorter distance.

I'm also skeptical of the 1700 RPM number on the curve, but until I see MLB statcast data I have no real reason to doubt it.
 
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