Digging Deeper: Hitter Batted Ball Analysis

April 24, 2021

Jon Anderson examines batted ball data through the lens of barrel rates and launch angle speed to determine fantasy baseball risers in the early portion of 2021.

The word "barrel" entered the fantasy baseball lexicon in 2015 and has quickly become one of the most often-referenced statistics to describe hitter performance. You will see barrels, barrel rate, and barrels per plate appearance talked about all over websites like this fine one. This is for good reason.

Prior to the onset of Statcast, we only had things like "hard hit rate" to go off of from great websites like FanGraphs. This was great to have, but it was limited. The Hard% metric did not give you much insight into anything other than whether or not a ball was being put in play while meeting a certain threshold. It was better than nothing, but hardly told the full story.

Now we have a colossal amount of data about everything that happens in Major League games. For every single pitch thrown, the Statcast system generates 80+ data points to describe what happened. The raw data set is enormous and provides near endless opportunities for insight. Today I want to dive in a little bit deeper into barrel rate and things similar to it. Then, we will review some players that are popping out in one way or another.

Launch Speed Angle

Every batted ball (hit into fair play) is classified into one of six categories by Statcast based on the launch velocity and angle. Using Python programming and the brilliant MatPlotLib package, I made a scatter plot displaying how this works. Here's it is:

Here's a description of each classification:

1. "Weak" - Balls hit below 60 miles per hour at any angle.
2. "Topped" - Balls the hitter hits right into the ground, with the angle requirement changing as velocity increases.
3. "Under" - Balls hit right into the air, with the angle range changing as velocity increases.
4. "Flares" - These are line drives that don't travel very far. You can see a 100+ mph ball can still be considered a "flare" if the angle is low enough.
5. "Solid" -  These are right on the fringe of being "barrels" but just don't quite make the cut because of velocity or angle (or both).
6. "Barrels" - These are the money makers, the most successful batted balls. They must be 97.5+ mph at a pretty thin (but still variable) angle range.

You can see from the plot that it's a really nuanced system. The classifications consider both angle and velocity and don't just classify in black-and-white terms.

Here's how these different launch speed angle classifications break down by the results:

89% of the league's 606 homers (as of April 22nd) have been classified as barrels. You can see the big disparity in slugging percentage shown in the table as well. If you are a hitter, you really want to be hitting fours, fives, and sixes here.

Now let's get to what you came here for, the leaderboard. Here is an interactive table of all players with 20 or more batted ball events, ranked by Barrel Rate. The Brl% column is just their barrel rate, the 5-6% column is barrels+solid, and the 4-6% column is flares+solid+barrels - all divided into their total BBE. You can sort the columns, flip through the pages, or search for a player.

Keep in mind the results table we showed above, hitting a bunch of flares is good for batting average but not good for slugging (you cannot hit a homer on a flare). Someone near the top of the list in 4-6% above might not be a great power hitter if they're just hitting a bunch of flares (which often go for singles but don't usually go for extra bases).

There were 25 different players with 20+ BBEs and no barrels, you can see those names by sorting by Brl%. These are guys like Andrelton Simmons, Myles Straw, Eric Sogard, David Fletcher, Nick Madrigal, etc. You might get some good batting average out of them (as shown by their often high number of flares), but they are not sources of power. Some more interesting names that have yet to achieve a barrel: Michael Conforto, Gavin Lux, Franchy Cordero, and James McCann.

If you sort by 4-6% and see the lowest numbers, these are players that are all just having miserable seasons at the plate. Kevin Newman leads the way with just 14.5% of his batted balls falling into one of the advantageous categories. He is hitting just .172 and slugging .207 this year after a spring where pitchers could hardly get him out.

Strikeouts, Though?

One trap that we fall into a lot is not considering the denominator in the equation. All of what you see above is using just batted balls as a denominator. If a hitter goes 1/10 with a barreled homer and nine strikeouts, his Brl% will be 100% and he will look like a stud, the other nine at-bats are ignored because he didn't put a ball into play. It's really important to factor in the strikeout rate here.

Here's a scatter plot of each player's solid+barrel rate (the 5-6% column above) vs. their strikeout rate. The best hitters are the ones with high values on the x-axis (5-6%) and low values on the y-axis (K%). You can mouse over each dot to see which player the dot represents.

There are just four players above the 85th percentile in both categories. Those players are Miguel Cabrera, Juan Soto, Joey Votto, Ronald Acuna Jr., and Freddie Freeman. As a general rule, anybody near the top in the 5-6% with a strikeout rate below 25% is going to be a very successful player.

What you see above is a great way to spot hitters with sustainable production. Both of these categories are pretty sticky (meaning what you see after a month or two of the season will be indicative of the future in most cases), and are directly correlated with fantasy success. Keep eye on these categories.

I'll be back with more posts like this every week here on RotoBaller, thanks for being here, and happy barrel hunting!

Download Our Free News & Alerts Mobile App

Like what you see? Download our updated fantasy baseball app for iPhone and Android with 24x7 player news, injury alerts, sleepers, prospects & more. All free!

More Sabermetrics & Statcast for Fantasy Baseball