Image credit: Cubs OF Owen Caissie (Photo by Chris Bernacchi/Diamond Images via Getty Images)
The advent of publicly available Statcast data has allowed advanced data and measurements to become a larger part of the conversation around the game of baseball. The ability to measure a variety of traits around a hitter or pitcher’s abilities gives us a better idea of their true talent level.
Exit velocity measures in particular have become as common in baseball conversation and content as batting average or on-base percentage. The ability to measure a player’s average exit velocity gives us a good idea of how hard a player hits the ball. Hitting the ball hard has proven to correlate directly with slugging and production in general.
We look at a variety of exit velocity metrics including average exit velocity, 90th percentile exit velocity and max exit velocity. Average exit velocity captures the consistency of hard contact and gives us a good idea of how hard a player hits the ball.
90th percentile exit velocity goes a step further looking at the top 10% exit velocities. This gives us a measure of a player’s high-end power and has proven to be more predictive of power in following seasons than average exit velocity.
Dylan White’s RoboScout tool identified hitters at the upper levels to put on your radar.
Access to exit velocity data in the public space is more limited when dealing with minor leaguers. Baseball America has gained access to MiLB batted ball data over the last few seasons through the help of sources. This has allowed us to study trends in batted ball data among minor leaguers on a micro and macro level.
We’ve learned that players on average add four mph to their average exit velocity between the ages of 18 (82.4 mph) and 22 (85.9 mph). There’s a similar progression in 90th percentile exit velocity, which jumps an average of 3.4 mph between 18 (98.1 mph) and 22 (101.5 mph). Both metrics grow the most for players over that four-year period and begin to stabilize after 22 years of age, with little to no gains after.
Some of this is because many of the best hitters and power hitters graduating from prospects to big leaguers after age 22. This would likely account for a number of prodigious hitters being removed from the sample before age 23 and many of those hitters likely possess the best power tools.
There is rapid progression between those ages, but an average jump of mph is expected. So what does it tell us when a player sees a jump of several mph year over year?
When dealing with prospects, you’re dealing with rapidly progressing human beings that make physical and skill-based gains in small periods of time.
Today we’ll examine the biggest exit velocity gainers in 2023, using average exit velocity and 90th percentile exit velocity to look at who gained the most power year over year. In order to make sure we’re looking at a similar sample size for each season we set the plate appearance minimum to 300 or more PAs in each of the last two seasons. This also helped to eliminate a large number of complex level hitters who tend to see the largest jumps year over year.
Finally, we listed isolated slugging as a way to measure power production year over year and the amount of percentage points gained. This gives us a good idea of whether or not the added exit velocity translated to results.
Average Exit Velocity Gainers
|PLAYER||ORG||ExitVel22||ExitVel23||EV avg +/-||ISO 22||ISO 23||ISO +/-|
|Victor Mesa Jr.||MIA||84.6||90.9||6.3||.102||.170||.068|
|Robert Hassell III||WSH||85.3||90||4.7||.133||.101||-.033|
- On average players in the top 20 of exit velocity mph gained saw a .041 jump in isolated slugging. That’s a fairly significant jump and equivalent to a full number grade on the 20-80 scouting scale.
- Only four players among the top 20 gainers saw a drop in isolated slugging and only Robert Hassell III’s .033 drop seems to be significant.
- Many of the top breakout hitting prospects from 2023 are among the top 20. That includes Coby Mayo, Owen Caissie and Abimelec Ortiz. All three can likely credit their exit velocity gains with having a hand in their respective jumps in production.
- Mayo and Caissie are particularly notable. They were already producing above-average exit velocity data in 2022. Their gains this season pushed them into double-plus raw power territory.
- Abimelec Ortiz’s ISO jump of .171 points is the largest on the list. He gained 5 mph of exit velocity.
- Gains in exit velocity have proven to not only correlate with production but also improvement at the skill level, chiefly bat speed.
- The biggest gainer in the list Jacob Young went from a league average player in Low-A as a 22 year old in 2022, to a major leaguer in 2023 by August. Certainly his power gains had a hand in his successful climb to the game’s highest level this summer.
90th Percentile Exit Velocity Gainers
|PLAYER||ORG||90%EV22||90%EV23||90% +/-||ISO 22||ISO 23||ISO +/-|
|Victor Mesa Jr.||MIA||100.6||104.4||3.8||.102||.170||.068|
- There’s a wide range of power profiles included within this chart. There are nine players included on this list that improved from 30-grade power based on 90th percentile EV to 40 or even 50-grade power.
- In an odd coincidence, the top 20 90th percentile gainers had the same number of hitters see a drop in isolated slugging year over year.
- Of the four hitters who saw a drop in isolated slugging, only Damon Keith and Endy Rodriguez were substantial drops. Perhaps this puts Rodriguez’s down season in a new light.
- Keith, on the other hand, may have seen a drop in power production due to environmental factors. Keith spent 2022 at Rancho Cucamonga of the California League, while he spent 2023 in the Midwest League. His drop in contact and rise in strikeout rate ultimately dragged his numbers down despite the added power.
- In another coincidence, the average jump in isolated slugging year over year was the same for the top 20 in average exit velocity and the top 20 in 90th percentile exit velocity.
- There’s a few players that show up on both lists including Abimelec Ortiz, James Triantos, Victor Mesa Jr., Sammy Siani and several others. This is a clear sign that their power gains were across all standard deviations, meaning they added to their top end power and their median.