Anecdotally, we can all intuit that the faster a player is the better off he is on batted balls in play. The question for me has always been, “By just how much are they better off?” So, I set out to try and find that answer.
To discover the impact of Sprint Speed on a player’s statistical output I took every competitive Batted Ball Event (BBE) in the Statcast era (2015-2020) and categorized them by Ground Balls, Line Drives, Fly Balls, and Pop-ups. All Home Runs and Sacrifice Bunts were removed as they were neither in play or competitive. The BBEs were further broken down by the Exit Velocity (EV), Launch Angle (LA), the batter’s handedness, and whether the ball was pulled, centered, or hit to the opposite field. In analyzing this data we can establish an average outcome for each combination of BBE variables. We call this average outcome the expected stats or xStats. Once we have the xStats for each set of BBE variable combinations we can then compare them to the actual stats that were generated at each Sprint Speed tier. Sprint Speed by Statcast measures a player’s speed by ft./sec. and the Sprint Speed tiers that we have chosen are 30 ft./sec. and above on the high end, 23 ft./sec. and under on the low end and each tier in between is separated by 1 ft./sec. The reason why 30 ft. /sec. and above and 23 ft. sec. and below were chosen as cutoffs are because there are a scarce number of BBE’s at 31 ft./ sec. and 22 ft. /sec. to obtain meaningful data. The median Sprint Speed for all years is 27.3 ft. /sec. “RCON” is expected Runs based on the expected contact results. The Sprint Speed factors are based on a standard 100 scale, meaning “100” is the league average. Any number above or below 100 is considered a % above/below league average. An example would be that All Batters with a 30 ft. /sec. Sprint Speed and above had an xAVG of .299 but actually hit .315. Actual AVG of .315 / xAVG of .299 = 1.0535. or, 105.
All Batters | All Batted Ball Events
The above chart aligns with what we might expect. For every speed tier above the median of about 27 ft. /sec. the Batting Average goes up versus the expected Batting Average, as do Triples and RCON. Conversely, for every speed tier below the median the Batting Average, Triples and RCON go down versus the expected outcome. Overall, we can expect hitters with above-average speed to hit between five to sixteen points higher on balls in play and to have 1.27 to 2.67 times the number of Triples as the player with average speed. With the slowest players, we see their number of Singles increase over the expected as they forego the extra bases. Below are the actual numbers versus the expected numbers for Batting Average and Triples by Sprint Speed.
All Batters | Ground Balls
As we saw with the All Batters, All Batted Ball Events chart for every speed tier above the median of about 27 ft. /sec. the Batting Average, Triples, and RCON go up versus the expected and for every speed tier below the median the Batting Average, Triples and RCON go down versus the expected. However, with Ground Balls, it’s even more pronounced in both the percentage impact as well as the number of categories that are impacted. With Ground Balls, Singles and Doubles are added to the list of categories that are directly affected by the player’s Sprint Speed. This tracks as Ground Balls are not impacted by whether the fielder caught the ball before the player’s speed comes into play, as it is with Line Drives and Fly Balls. The chart below shows that hitters with above-average speed hit eleven to thirty-eight points higher on Ground Balls and have 1.29 to 3.71 times as many Triples as their average speed counterparts. The slowest players in the league did not hit a single Ground Ball that resulted in a Triple from 2015-2020.
All Batters | Line Drives
We are still seeing the impact of Sprint Speed, however, it’s not as pronounced as with the Ground Balls. There’s virtually no correlation with Batting Average but because many line drives reach the outfield we can see that the BBEs that are typically just Singles for the slower players are turned into Doubles and Triples by the faster players. These additional bases gained by the speedier hitters turn into more expected Runs. The slower players settle for Singles and don’t take that extra base.
All Batters | Fly Balls
Again, the chart above shows some impact by Sprint Speed but it’s basically just in the Triples category. Fly Balls in play were only hit for a .107 Batting Average in 2015 through 2020 so there’s less and less of an opportunity for the hitter’s Sprint Speed to have an influence.
Right-Handed vs. Left-Handed Batters | Ground Balls
As we can see above, the average speed and more elite speed Left-Handed batters slightly outpace their Right-Handed batter speed tier counterparts in just about every expected stat. Intuitively, this would make some practical sense as Left-Handers are typically starting about 2 ½ feet closer to first base than Right-Handed batters. However, if you look at the chart below, Right-Handed batters hit a full twenty points higher than Left-Handed batters on Ground Balls. Why? The answer is twofold. First, both Right-Handed batters and Left-Handed batters pull the ball more than 40% of the time (44.4% and 42.2%, respectively). But, when Right-Handed batters pull the ball on the ground it’s a much longer throw across the diamond than when Left-Handed batters pull the ball. Second, although Right-Handers actually pull the ball more than Left-Handers, MLB teams deploy an infield shift against RHBs only 14.7% of the time while LHBs see an infield shift 38.8% of the time. The combination of the longer throws and fewer fielders to the pull-side of Right-Handers leads to more hits while the shorter throw and more fielders to the pull-side of Left-Handers have the inverse effect.
The Speed Bobbles | Sprint Speed Impact on Errors
Once again we can see the impact of Sprint Speed on the game. On Ground Balls, as Sprint Speed increases from the median Sprint Speed of about 27 ft. /sec., we see the Total Percentage of Errors committed rise from 2.4% to 3.0%. As we see Sprint Speed decrease from the median we see the Total Percentage of Errors committed fall from 2.4% down to about 1.7%. We can also see the impact of the batter’s handedness as errors are made at a higher clip against Right-Handers and that difference is exacerbated as Sprint Speed increases. This makes sense as fielders have the longer throws against Right-Handers and they feel the need to rush their plays against the faster players. On Line Drives and Fly Balls, Sprint Speed made no meaningful difference as the error rates were about 0.2% across almost all tiers. A quick credit to my friend Christine Hantgin who far too often has to hear me talk about my article ideas while relaxing on our porch with my wife and her husband. I do know now that she actually listens to my ramblings because as I was explaining this research to everyone she said, “You should call the errors caused by the fast guys “The Speed Bobbles”.” I liked it, so I did.
What Does it All Mean?
*BBE and Hits do not include HR’s