I publish a weekly article called “Statcast Standouts throughout the regular season.” You can find those articles here if you are interested. In each of those articles, I break down players who stand out based on statcast data from Baseball Savant. I try to explain why each stat discussed in those articles was practical and helpful for Fantasy Baseball analysis.
It is now the offseason; player evaluations for 2022 have begun. Baseball Savant and Fangraphs are both likely a resource you use when evaluating players. You may see stats on those websites that you do not know what they mean. This article series has the intention to help you learn more about specific statcast data and other stats and how you can use that data to analyze players for Fantasy Baseball. It is important to note that a player’s statcast profile does not paint the entire picture. It is just another tool in the toolshed. So, let’s look at a couple of stats and how they are practical for Fantasy Baseball.
Statcast Data and What It Means
As I prefaced earlier, statcast data does not tell everything about a player. This profile you see below also shows minimal about a player because many of these stats tell you similar things. It is not enough to look at a player’s profile and say: “Oh, all the sliders are red. This player is good.” Knowing what these statistics mean will take you a long way.
Baseball Savant Profile
When you first get to a player’s profile on Baseball Savant, you will find a nice picture of the player (when the lockout ends) with the player’s position, whether they bat/throw right or left, the player’s height, weight, and their age. If you move to the middle of the page, you will see MLB percentile rankings. This list lists several different statcast numbers and their percentile rankings among hitters or pitchers. Finally, to the far right of the page, you’ll see a hitters spray chart on just batted balls that became hits.
In the picture above, you can see that Juan Soto ranks exceptionally well in every hitting category. When a player ranks well in a category, you will see color and a percentile. If a player ranks highly, that data set will be red. As a player fades toward the 50th percentile, that color will fade to neutral and eventually blue. A slider will be blue on the far extreme if a player ranks poorly in a category.
It is easy to look at a statcast profile like Soto’s full of red and automatically assume that the player is good. Duh, Juan Soto is good, more like the best player in baseball good. The same can be said for a player with a lot of blue in his profile. While it is likely true, it is worth understanding what each stat means and how it correlates to actual stats that matter for Fantasy Baseball.
If you scroll down on the player’s profile page, you will find a player’s stats for both the current/previous season and the player’s career. Then you see the statcast data. This is ranked on the sliders at the very top of the page. This view gives you a nice overlook at how a player may have improved or regressed each season.
Right below the statistics is a nice chart. The default view is the percentage of each pitch type a player saw in a season. The pitch types are broken down by fastball, breaking ball, and offspeed. The pitch tracking section below the chart shows how a player performed based on pitch type.
This chart is handy for a lot of things. If you can click into the drop-down box labeled “PITCH %,” you can change the input to a variety of statistics, including all statcast data. In most cases, I switch “PITCH GROUP” to “ALL PITCHES,” which provides an excellent overview of how a player has performed. You can look at a player’s performance over the season, month, or by game. If you are a visual person like me, you will likely find this page section very useful.
This is a generic overview of a player’s statcast profile page on Baseball Savant. There is much more down the page. But what is at the top is what I generally find most useful, especially from a statcast standpoint. Let’s talk about some metrics and how they are helpful.
Average Exit Velocity
Exit velocity is one of the more simplistic statcast numbers. Essentially, exit velocity is how fast, in miles per hour, a batted ball is hit. Average exit velocity is calculated by dividing the sum of all exit velocities by all batted ball events. Having a high average exit velocity is a skill a player can own. It means a player is hitting the ball hard and has a higher probability of positive results.
Average exit velocity has a high correlation of being descriptive of a player’s wOBA, Home Run percentage, and ISO(Isolated Power equals Slugging Percentage minus Batting Average). Average exit velocity has the strongest predictive correlation with future batting average when projecting a player’s future performance.
When testing it against max exit velocity, average exit velocity is more descriptive of home run rate and home runs per batted ball event. Looking at home runs per batted ball event last year, we see an R2 of just .272 with max exit velocity. It is interesting because max exit velocity seems like it would be a better indicator of home runs.
You can also find R2 for home runs per batted ball event against average exit velocity much stronger at .352.
Average exit velocity can be useful for Fantasy Baseball when looking at a player’s performance and evaluating whether they are sustainable. Let’s say a hitter has a .185 batting average over the first month of the season but leads the league in exit velocity. It is possible they have gotten unlucky and could create a good buying opportunity from a Fantasy standpoint. On the flip side, a player off to a hot start but has just an 85 mph average exit velocity could show a potential decline and be a good selling opportunity.
My studies show that in the juiced ball era, the average exit velocity did not matter as much. Another study found that MLB began juicing the balls after the 2015 season. The correlation between home runs and average exit velocity was lower in 2016 through 2020. Surprisingly, after the ball was “deadened” for 2021, the direct correlation between average exit velocity and home runs was higher. Who knows what MLB will decide with the baseballs in 2022, but one thing is sure. If it is a “deadened” baseball, you will likely see hitters with lower average exit velocities hit fewer home runs.
Average exit velocity is not always the most valuable stat, but it does have its purposes. It is probably the most quoted statcast metric, but know what it is helpful for. Let’s take average exit velocity a step further.
Exit Velocity(Line Drives/Fly Balls)
Let’s look at a hitter’s average exit velocity, but only on line drives and fly balls. Because average exit velocity includes all batted ball events, weakly hit grounders can easily skew it. If you are looking to forecast a hitter’s power, exit velocity on FB/LD is more descriptive and predictive of a player’s power output.
To find this on Baseball Savant, go to the statcast leaderboard and exit velocity and barrels tab. From there, you can sort by EV: FB/LD. You can see in the chart above the leaders from the 2020 season. While Shohei Ohtani had a 93.9 mph exit velocity, that number jumped to 100.4 mph on fly balls and line drives. This helps explain Soto’s robust ISO(.335) and home run total(46 in 639 plate appearances).
You can also take this further and look at exit velocity on just flyballs. Many of the same players show up on this leaderboard, but Mike Zunino led the way in 2021 at 100.3 mph. Shohei Ohtani (99.6 mph), Tyler O’Neill (98.9), Joey Gallo(98.8), and Fernando Tatís Jr(98.7) follow Zunino.
If you are looking to use average exit velocity to evaluate and project a hitter, I recommend using average exit velocity on line drives and fly balls. Studies have proven it is a little more sticky than general exit velocity. It does not matter how hard a player hits the ball if it is drilled into the ground. A player that hits the ball in the air and hits it hard is much more likely to have a better power output.
If you are looking for a more descriptive and predictive metric of future power output, average exit velocity on line drives and fly balls is the way to go.
On Soto’s profile listed above, you will see hard-hit percentage next to exit velocity. Statcast defines a “hard-hit ball” as one with an exit velocity of 95 mph or higher. A batter’s hard-hit rate merely shows what percentage of batted balls are hit 95 mph or higher. Why does this matter? Well, the 95 mph exit velocity threshold shows where things begin to matter. The chart below is from MLB.com and shows wOBA against exit velocity. You can see the trend.
In 2021, hard-hit batted balls produced a leaguewide .500 batting average, a 1.015 slugging percentage, and a .625 wOBA. On the flip side, batted balls hit below 95 miles per hour produced a leaguewide .221 batting average, a .263 slugging percentage, and a .208 wOBA. These statistics make it pretty clear there is a value in hard-hit rate.
Last season 17 hitters eclipsed a 50 percent hard-hit rate. You can find that leaderboard below.
I have attached the 2021 hard-hit rate leaderboard above. Typically, players with a high hard-hit rate perform well across the board. Most of these hitters also go incredibly high in drafts. Outliers include Miguel Sanó, Josh Donaldson, Nelson Cruz, and Josh Bell. All have various reasons they are not high draft picks for Fantasy Baseball, but all have the upside to be solid contributors.
Using hard-hit rates to evaluate the legitimacy of a player’s performance is a great thing to do. Hard-hit rate also tends to stabilize year-to-year so that you can use it as a predictive measure as well.
Well, thanks for tuning in for part one of “Statcast 101.” I will have plenty more articles coming your way on these topics. I hope you find use in them in helping you use statcast data to win your Fantasy Baseball Leagues.
Media References: Baseball Savant, MLB.com
Fantrax was one of the fastest-growing fantasy sites of the last few years, and we’re not stopping now. With multi-team trades, designated commissioner/league managers, and drag/drop easy click methods, Fantrax is sure to excite the serious fantasy sports fan – sign up now at Fantrax.com.