Investigating the Two-Strike Approach
Should hitters shorten up with two strikes?
Since their release last May, Statcast’s new bat tracking metrics have provided analysts and fans with intriguing new ways to measure the offensive performance of Major League Baseball hitters. Metrics such as bat speed, blast percentage, and the recently introduced/forthcoming measures of contact point and attack angle offer deeper insights into a hitter’s skill level, especially in smaller sample sizes, than existing exit velocity metrics. In addition to analyzing offensive performance on an individual player level, these metrics allow analysts to observe offensive trends on a macro league-wide level. Since the advent of pitch tracking, we have been able to analyze year-to-year pitching strategy trends, and these bat tracking metrics will allow the public to analyze year-to-year offensive trends on a more granular level.
From youth baseball up to the professional level, “shorten up with two strikes” has been a common piece of advice that coaches have given to hitters to alter their approach at the plate when they are in a two-strike count. By “shortening up”, the hitter swings the bat with less intensity, becoming more contact-oriented to theoretically reduce their chances of striking out via a swing-and-miss. In short, the hitter is trading off power for contact, with the assumption that more power leads to more swing-and-miss. Over the past few seasons, some have questioned whether or not the two-strike approach exists at the Major League level, given the rise in strikeouts across the league. Using bat tracking data from the 2024 Major League Baseball season, this article will investigate whether hitters actually alter their “swing effort” with two strikes, and, more importantly, if this adjustment is beneficial or detrimental to their overall offensive performance.
Does the Two-Strike Approach Exist?:
First, we will need to determine whether or not a two-strike approach exists at the Major League level. To determine this, I calculated a new metric for each swing taken during the 2024 season, “swing effort”, which is the bat speed of a given swing divided by the player’s maximum bat speed. For a two-strike approach to exist, the average swing effort across Major League Baseball would have to be lower in two-strike counts than any other count state.
As shown by the tables above, a distinct two-strike approach does appear to exist across Major League Baseball. On two-strike counts, hitters, on average, swing at 81.1% of their maximum bat speed, compared to the 84.5% swing effort they display when they are ahead in the count. Hitters are ready to attack on 3-0 counts, swinging at 86.6% of their maximum bat speed on average, while hitters become defensive in 0-2 counts with an average swing effort of 79.6%. Given the significant difference in swing effort (3.4%) between counts where the hitter is ahead and two-strike counts, I believe that this data suggests that a distinct two-strike approach exists around Major League Baseball.
Are there more variables that could be used to determine if a two-strike approach exists? Definitely! Bat speed is only one piece of the puzzle, and perhaps additional data such as hand position, stance position, and/or location-adjusted swing length can provide additional insight alongside swing effort into how much a player “shortens up” with two strikes. Given the data that currently exists publicly, however, it can be concluded that hitters across the league swing with less intensity in two-strikes counts, likely proving the existence of a league-wide two-strike approach.
Is Shortening Up an Optimal Strategy?:
With it being established that the two-strike approach does indeed exist across Major League Baseball, the next question to ask is whether “shortening up” with two strikes is an optimal strategy for hitters across the league. To answer this question, I decided to plot the relationship between swing effort and wOBAcon, and swing effort and Whiff% on two-strike counts during the 2024 Major League Baseball season.
As shown by the table above, there appears to be little relationship between swing effort and Whiff% across the league in two-strike counts, and hitters appear to swing and miss slightly less when they swing harder in these count states. In addition, wOBAcon significantly increases as hitters increase their swing effort in two-strike counts. The relationship becomes quite noisy when the sample size becomes smaller past ~92% swing effort, but there is approximately a .200 wOBAcon difference between 75% swing effort and 90% swing effort in two-strike counts.
Analyzing hitters can become a very nuanced topic, and there are certainly more metrics needed to fully capture a hitter’s true talent level besides bat speed and swing effort, however, given the bat tracking data that is currently publicly available, it appears that lowering swing effort with two strikes is generally not an optimal strategy for hitters across the league. Does this mean that every hitter across the league should go full-throttle and swing for the fences when they are behind in the count? Not necessarily. There are likely secondary effects that can occur from “shortening up” (perhaps hitters demonstrate improved swing decisions when “shortening up”), and some hitters do experience a decrease in whiff rate when decreasing their swing effort with two strikes (Cody Bellinger and Nick Castellanos are two notable examples). This analysis, however, does provide insight that when a hitter is experiencing an increase in whiff rate and a decrease in wOBAcon while shortening up in two-strike counts, perhaps they can alter their approach to swing with more intent in these count states to improve their overall level of production.
The table above depicts six hitters who I believe should increase their swing intent in two-strike counts this season. Harrison Bader, Jeimer Candelario, and George Springer are three players who I believe should swing with more intensity in two-strike counts, as they experience a notable increase in whiff rate and decrease in wOBAcon in these count states despite “shortening up”. Luis Robert Jr. and Jake Burger swing with high intensity both when they’re ahead and when they are in two-strike counts, however, their results decline when they toggle down their swing effort with two strikes. Otto Lopez had the largest swing effort delta in Major League Baseball last season (minimum 400 plate appearances), which resulted in his whiff rate increasing by 10.8% in two-strike counts compared to when he was ahead in the count.
While swing effort is certainly not the sole determinant of hitter success, these examples illustrate that for some hitters, the traditional two-strike approach may be contributing to a decrease in their production in two-strike counts. As teams and analysts continue to integrate bat tracking data into player development and evaluation, tailoring swing strategies on an individual basis rather than universally “shortening up” could lead to an increase in offensive production in two-strike counts.
Concluding Thoughts:
Is this enough evidence to declare that all hitters should move on from the two-strike approach and swing with the same intensity as when they're ahead in the count? Probably not. As mentioned earlier, there are likely secondary effects that occur when shortening up with two strikes, such as improved swing decisions, and perhaps the new batting stance data from Statcast can provide additional insight on the efficacy of the two-strike approach if/when the data is released on a pitch-by-pitch level. With that being said, given the strong positive relationship between swing effort and wOBAcon and the relatively weak relationship between swing effort and Whiff% in two-strike counts, it appears likely that the two-strike approach is not the optimal approach to utilize in two-strike counts on a macro level.
I will be paying particular attention to the swing effort breakdown by count state across the league this season to see if Major League teams believe that hitters should swing with more intensity in two-strike counts. If the average swing effort with two strikes increases to ~82.0% this season, then perhaps we can declare that the league is changing their philosophy regarding the two-strike approach. Bat tracking data is poised to improve the public’s understanding of the factors that contribute to offensive production over the upcoming seasons, and this two-strike approach analysis is one example of how this data can open new avenues of offensive analysis and provide actionable insights into improving offensive performance.
Thanks for reading!
Follow @MLBDailyStats_ on X and Adam Salorio on Substack for more in-depth MLB analysis. Photo credits to Kevin Souza / USA Today Sports.