Pitching Data Dive: East Valley Summer ID
June 11, 2026
Mesa, AZ – ARIZONA ATHLETIC GROUNDS – The East Valley Summer ID, our first Summer ID event of the 2026 season, took place at Arizona Athletic Grounds and featured quality talent from across the board in the 2027–2039 classes. The event included a full pro-style workout with players going through batting practice and defensive evaluations while collecting data through TrackMan, BLAST Motion, VALD 60-yard sprints (with splits), and more. Pitchers also threw bullpens with detailed metrics captured including velocity, spin rate, and movement profiles. A number of familiar names continued to trend upward while several new prospects made strong impressions throughout the workout.
We continue our post-event coverage with a look at the statistical leaders from each category recorded during the event.
To view the full stats from the event, CLICK HERE.
JUMP TO: FASTBALL | CURVEBALL | SLIDER | CHANGEUP
FASTBALL
MAX VELOCITY
Max Fastball Velocity: This metric calculates the speed of the pitch as it’s released from the pitcher’s hand.
HIGHEST AVG. SPIN RATE
Spin Rate: This metric calculates the rate of spin on the baseball as it leaves the pitcher’s hand, measured in revolutions per minute (rpm). Historical data shows that high-spin fastballs lessen the impact of gravity, allowing for more ‘rise’ (or less fall, in other words) as it carries through the zone. Low-spin fastballs typically indicate the pitch has greater horizontal action, often making it tougher to square up, but generally easier to make contact with, leading to more ground balls, while high-spin fastballs show a higher correlation with swings and misses.
HIGHEST AVG. IVB
Induced Vertical Break: Used in short form as “IVB,” this metric is most important on fastballs for creating rise and on curveballs/changeups for creating depth. It also has some use when measuring sliders and cutters as well. Sliders tend to be closer to zero inches while cutters are generally between 5 and 15 inches. Usually fastballs and curveballs with large IVB have higher spin efficiencies as well. Sliders generally have very little (closer to zero) IVB and very low spin efficiency. You could also categorize IVB into spin rate as this is part of the “useful movement” you’re looking for, and it’s also important to consider the pitch’s velocity as well as its release height when evaluating IVB measurements against each other.
AVG. HORIZONTAL MOVEMENT
Horizontal Break: Outlined on TrackMan’s own website: “... horizontal movement is measured in inches between where the pitch actually crosses the front of home plate side-wise, and where it would have crossed home plate side-wise if had it traveled in a perfectly straight line from release. A positive number means the break was to the right from the pitcher’s perspective, while a negative number means the break was to the left from the pitcher’s perspective.”
HIGHEST STRIKE ZONE RATE%
For some context, in 2023 MLB pitchers averaged an In Zone% of around 49 percent in live game settings measured across all pitch types, according to Statcast.