In today’s game of baseball – more than ever velocity is king. If you watch a MLB game it is commonplace to see multiple pitchers for both teams throw 95+ MPH. This has had a trickle down effect to MILB, college, high school and youth levels with everyone throwing for the gun. SO how can we evaluate a pitcher who does not throw as hard as his contemporaries? By using a device called Rapsodo. Rapsodo is a machine that sets up behind the plate while you throw, it is connected via bluetooth to either a Ipad or PC and gives you instant feedback. We are able to see the velocity, spin rate, spin axis, spin efficiency, horizontal and vertical break and also get an overlay of what the pitch did. Armed with this information and video we can quickly figure out why certain pitches work or don’t work. We can also tailor pitches to his skill set, depending on his release and how he spins the ball.

Training the next Justin Verlander?

I train a 15 year old multi-sport athlete (took 3-4 months off from throwing) who averages 72 MPH on his fastball and 60 MPH on his curveball. He has always pitched well, but when you look at his baseline numbers he does not blow you away. That velocity for most coaches would make them recommend he throw low in the zone, and pitch to contact. We have always known he has good stuff as a pitcher, but could never quantify it – now with Rapsodo we can.

What it tells us is he averages 2,000 RPM on his fastball and 2,352 RPM on his curveball.

What do those RPM numbers mean exactly and how are they useful? They tell us his spin rate.

Understanding a Baseball Spin Rate?

Spin Rate looks at how many revolutions per minute (RPM) the ball has during flight to the plate. It has been shown that the higher the spin rate of a pitch – the higher the swing and miss percentage is. By using Rapsodo, this allows us to evaluate a current pitchers pitches with more accuracy than the old “eye test”. When looking at MLB spin rates for fastballs and curveballs it breaks down to this:


Highest spin: 2,553 rpm, Rafael Betancourt

MLB average: 2,226 rpm

Lowest spin: 1,743 rpm, Jean Machi


Highest spin: 3,086 rpm,  Garrett Richards

MLB average: 2,308 rpm

Lowest spin: 1,302 rpm, Logan Kensing

To check out other pitches and how they work compared to velocity here is the article

Using the table above we can see that his fastball spin rate on average is a little but lower than MLB average, but that his curveball is higher! So how can a 15 year old kid have comparable spin rate numbers to MLB pitchers, but his velocity be so drastically different? When looking at average velocities for these two pitches, the athlete lags behind greatly:

MLB Average Fastball – 92.9

15 Year Old Athlete – 72.0

MLB Average Curveball – 78.2

15 year old athlete – 60.0

But here is the thing, we still don’t know exactly what causes high or low spin rates.

How to compare Spin Rates and Velocity

The next metric we use to evaluate pitchers is Bauer Units. Driveline Baseball created this unit of measurement to better compare spin rates at different velocities between pitchers.

For further reading

BU = Spin Rate (RPM)/Velocity (MPH)

Having this unit allows you to see how much spin is accompanied with the velocity of pitch.

So if two pitchers have a spin rate of 2400 rpm on their fastballs, but one throws 88 and the other throws 98, their Bauer Units will be different. The 98 mph BU number will be 24.6 and the 88 mph will be 27.1. Using the information above we can see that MLB average is a 92 mph fastball spinning at 2200 rpm. This makes the average Bauer Unit 23.9, which can be rounded to 24.

This allows you to see where you stand in comparison with MLB pitchers if you are a pitcher of a different level (youth, high school, College). It also gives us a guide of what type of pitches he should throw.  If he has league average Bauer Units he should look into developing a 2-seam, if they are above average then try to throw middle/up in the zone and if it is below average he should try to throw middle/down in the zone.

This athlete’s numbers then tell us this – Having a fastball that is 72 mph with a 2,000 rpm gives him a 27 BU. Meaning he is above average and should throw middle to up in the zone. Coupled with his curveball which is 39.2 BU, he should pretty much live in the top shelf of the strike zone and throw CB off of that. In comparison to a MLB pitcher we chose Justin Verlander of the Houston Astros (the players favorite team) Using his best fastball and curveball we are at:

Fastball 99 mph / 2,598 rpm = 26 BU

Curveball 82 mph / 3,064 rpm = 37 BU

Using this we can say as a pitcher he should try to emulate Verlander’s style of pitching of changing eye levels and pitch up and out of the zone with his fastball. As I said before – majority of coaches would tell this pitcher he needs to live down in the strike zone, and pitch to contact. Having this information drastically changes how he pitches in games, but also allows him to maximize his ability to spin the ball at a high rate.

How to continue with this athlete’s pitch and velocity development

When looking at video you can see some inefficiencies how he releases the pitch. Mainly being how his elbow spirals into releasing the pitch, where his chest lunges forward blocking his arm from fully unwinding. Over the next month to reduce the chance of injury – we will work on lead leg bracing and patterning how his upper body needs to rotate and move into pitch release. My question is when focusing on this change in clearing space for his arm to throw, will it harm or help his current pitch’s spin rates? My gut says the latter, because now that he has more freedom to move he allow himself to rotate efficiently in the upper half.

What makes this process so unique is the ability to make quick adjustments on pitch creation, which before was a time intensive process with a lot of “well, let’s see if this works”. Now we can quickly look at the information with video and say – “well, you are letting the curveball slide up your index finger on release of the pitch, causing it to be off axis and not spin as well.”  Pitchers when given this information and see themselves on video, make much quicker and long lasting adjustments. Knowing what they need to fix or change in a game rather than guessing or saying “My curveball just sucks”. It also allows players to see what the effectiveness of the pitch looks like, what the batter see’s vs what really happens. In the picture below, you can see two lines on the way to the plate. The full red line is how the ball actually moved and the dotted line is what the batter saw.

What you can see is that a batter saw the ball being close to the right handed batter’s box, but it really ended up in the left handed batter’s box.


P.S. If you live in the Austin area and want to have their pitching evaluated with Rapsodo please feel free to reach out to me!!

Scott Lacey