Introducing Opt_95: Identifying Hitters Who Outperform Their Expected Statistics
In my opinion, being able to identify undervalued players who have particular traits that can be further developed is one main component of running a successful Major League Baseball organization. The advent of advanced technologies, such as Trackman and Hawk-Eye, has allowed for a revolution in pitching analysis and development, while training methods such as Bat Speed training are beginning to “break through” as innovative ways to improve offensive performance.
When Statcast was implemented full-time into Major League Baseball stadiums in 2015, one of the main features of the technology was the ability to create expected statistics for each player based off of features such as exit velocity, launch angle, and sprint speed. These metrics have proven to be generally good indicators of player’s performance, and theoretically should be better methods of identifying outlier offensive performances than simply using BABIP, as these metrics take into account how hard each ball is hit and, in some instances, the speed of the runner. However, one flaw of expected statistics is that they do not take into account the spray angle of each batted ball, treating a pulled fly ball and an opposite field fly ball as the same batted ball event (assuming equal exit velocity and launch angle). This discrepancy has caused some players to outperform their expected statistics consistently, and in some cases display plus power despite possessing below-average batted ball metrics. In this article, I will be discussing the causes of this discrepancy between actual and expected statistics, and introduce a statistic that I have created that aims to identify which hitters outperform their expected statistics with some level of consistency.
Background:
Weighted On-Base Average (wOBA) is one of the best statistics to use when evaluating an offensive player’s performance as it uses linear weights in order to place a proper value on each offensive outcome, and the statistic forms the basis of how FanGraphs calculates the offensive production element of Wins Above Replacement. Given the importance of wOBA, the introduction of Expected Weighted On-Base Average (xwOBA) at the advent of the Statcast era brought some optimism that a more effective method of identifying offensive outliers had been created.
As mentioned earlier, a major flaw of xwOBA is that the metric does not take into account the Spray Angle of each batted ball, treating balls hit to the pull side, the opposite field, or straightaway equally the same. A recent article by Ben Clemens in FanGraphs first brought my attention to this phenomenon, and the findings he made in his article served as the basis for my further research:
I believe that this table is the most important part of the research performed by Ben Clemens, as there is a clear advantage for hitters to hit their fly balls to the pull side than any other part of the field on a batted ball with an exit velocity between 95–100 MPH. In this exit velocity range, the difference in wOBA between “Pull” and “Oppo” fly balls (.523) is the largest amongst all the other exit velocity groupings.
To some, this might come off as a “no kidding” type of finding. Of course, there is great benefit to pulling the ball in the air, and most observers have acknowledged this as a way to hit for power since the start of the Live-ball Era. This importance in this finding comes from the fact that xwOBA treats all of these spray angles as the same, which indicates that players who frequently pull fly balls within this exit velocity range are most likely underrated by xwOBA.
The most prominent example of a hitter who consistently pulls fly balls for home runs in this exit velocity range is Isaac Paredes of the Tampa Bay Rays. Since being traded to Tampa Bay prior to the 2022 season, Paredes has unexpectedly become a power machine, hitting 20 home runs in 2022 and 31 home runs in 2023. A simple look at Paredes spray charts over the past two seasons shows how Paredes is able to tap into this power by focusing on hitting fly balls to the pull side.
This power surge came as a surprise to many when Paredes was acquired by the Rays, since he was widely considered to be a contact-oriented hitter during his time as a prospect with the Detroit Tigers (55/60 Hit, 40/45 Game Power according to his FanGraphs scouting report). When examining Statcast data of all batted balls hit over the past three seasons, I have found that most home runs on pulled fly balls hit between 95–105 MPH exit velocity by right-handed hitters are hit on up-and-in Four Seamers and low-and-in Sliders. I hypothesize that this is due to hitters making contact out in front of the plate, being able to turn on these inside pitches with efficiency. While this data is not available to the public, Eno Sarris of The Athletic wrote a piece on this topic a few years ago which included many tidbits about the effectiveness of hitters making contact with pitches out in front of the plate:
As shown by the table above, it appears obvious to see what changes Isaac Paredes made to his approach against Four Seamers after he was acquired by the Tampa Bay Rays. Paredes has always been able to make contact against Four Seamers in the zone, but he was frequently swinging at them when they were located in low-and-in. Once he arrived at Tampa Bay, Paredes has focussed on aggressively swinging at high-and-inside Four Seamers, knowing that he has a plus ability to make contact on these pitches which allows for him to make contact out in front and drive these pitches for power to the pull side. Paredes also has a plus ability to make contact on down-and-in Sliders, and having this approach of sitting on up-and-in Four Seamers makes it easier for him to make an adjustment to properly identify and attack Sliders that “back up” on the pitcher. These are a few reasons why Isaac Paredes has been able to over-perform his xwOBA over the past two seasons and was able to hit 31 home runs last season despite posting a 28.8% Hard Hit Rate and 107.7 MPH Max EV.
Introducing Opt_95:
What if there is a way, with some level of consistency, that we can identify players that should outperform their expected statistics due to their ability to pull their fly balls at optimal exit velocities? This brings us to the main feature of this article, which is the introduction of my new statistic “Opt_95”.
Almost all baseball sites, such as FanGraphs and Baseball Savant, display breakdowns of each player’s batted ball tendencies (FB/LD/GB and Pull/Center/Oppo). While this can be an easy way to “ballpark” whether or not a hitter pulls the ball in the air with consistency, it requires making some assumption that may turn out to be false (in a hypothetical scenario, a player with a 45% Pull Rate and 45% FB Rate may pull all of their ground balls and hit all of their fly balls to the opposite field). Some websites, such as Alex Chamberlain’s Pitch Leaderboard, include a hitter’s Pulled Fly Ball Rate which is obviously a good metric of analyzing a player’s pulled fly balls. However, this statistic accounts for batted balls among all exit velocities despite the fact that we now know that there is more benefit to pulling the ball in the air in the 95–100 MPH exit velocity range, relative to other spray angles, than any other exit velocity range.
This leads us to Opt_95, which is calculated as the amount of pulled fly balls between 95–105 MPH exit velocity divided by the number of batted ball events between 95–105 MPH exit velocity. This allows us to determine which players optimize their batted balls between 95–105 MPH exit velocity more effectively, which may allow them to outperform their expected statistics with some level of consistency. I decided to expand the range of exit velocities for this statistic from 95–100 MPH to 95–105 MPH in order to create a larger sample size for each hitter, as well as to take into consideration that there is still a benefit to pulling the ball as opposed to hitting it straight away in the 100–105 MPH exit velocity range.
Finally, in order to create a leaderboard of which hitters have the best Opt_95 over the past three seasons, I filtered the data based on the following criteria. Each hitter had to have at least 75 batted ball events between 95–105 MPH exit velocity and a Max. Exit Velocity below 110 MPH in a particular season. This allows for us to analyze a subset of players that hit plenty of balls with this exit velocity range, and do not hit the ball at an exit velocity where spray angle’s importance is diminished. Here is the Opt_95 Leaderboard for the 2021–2023 seasons:
As expected, Issac Paredes reigns on top of this leaderboard with a 25.7% Opt_95 in 2023, resulting in him overperforming his xwOBAcon on fly balls by .250. If I raised the Max. EV threshold to 110.5 MPH, Paredes would also place 2nd on this leaderboard with a 21.2% Opt_95 in 2022, outperforming his xwOBAcon on fly balls by .202. Wilmer Flores has had 3 of the Top 10 Opt_95 performances since 2021, and known pulled fly ball maestro Marcus Semien appears on this leaderboard twice.
While this leaderboard does pass the eye test of being indicative of whether a player can consistently outperform their expected statistics, this data does need to undergo a few tests before we can establish that Opt_95 is a statistically significant predictor of xwOBA overperformance. First, I will plot each player’s Opt_95 and wOBAcon(FB)-xwOBAcon(FB) difference and evaluate the R-squared and P-value of a regression between these two variables.
There are two main takeaways that I can observe from this graph. First, I am very impressed by the low P-value between these two variables. This indicated that there is a statistically significant relationship between a player’s Opt_95 and the difference between their actual and expected weighted on-base average on fly balls. This is important because it can be stated with confidence that the amount of pulled fly balls a hitter hits between 95–105 MPH has an effect on whether or not he can outperform his expected statistics.
Second, there are a couple ways to interpret the R-squared value of .2477, which indicates that ~25% of the variation in each hitter’s difference between their actual and expected weighted on-base average on fly balls can be explained by Opt_95. One interpretation of this is that while Opt_95 is a good measure to determine whether a hitter overperforms their xwOBA, it shouldn’t be used as the sole variable in approximating the size of the difference between a hitter’s actual and expected statistics. Another interpretation is that, as shown by the plot, a hitter is very likely to outperform their expected weighted on-base average on fly balls if they exhibit an Opt_95 greater than 10%. Therefore, in my opinion, if a player with a Max. Exit Velocity under 110 MPH is attempting to produce more power and outperform their expected statistics, they should aim to produce an Opt_95 of at least 10% in order to have a probable chance of achieving their objective.
Next is an analysis of the year-to-year stickiness of Opt_95. For this analysis, I removed the Max. Exit Velocity filter and analyzed each hitter’s change in Opt_95 from one season to the next (min. 75 batted ball events between 95–105 MPH in successive seasons). Similar to the previous graph, this analysis results in a promising P-value and a R-squared that is up to interpretation. While the P-value indicates that there is a statistically significant relationship between a hitter’s Opt_95 from one year to the next, this relationship only accounts for ~40% of the year-to-year variance. One takeaway I have from this graph is that a player is likely to remain over the 10% threshold during the next season if they achieve at least a 15% Opt_95 during the present season.
Sure, I would like the R-squared values to be higher in both graphs, but the P-values are promising and indicates to me that Opt_95 can be used at least as a tool for evaluating player who consistently over perform their expected statistics and for identifying players who could produce more power output in the future despite underwhelming batted ball statistics. Here are a few intriguing players that came up over the course of my research:
Wilmer Flores (1B/DH — San Francisco Giants):
While the inspiration for this article was the offensive performance displayed by Isaac Paredes over the past two seasons, Wilmer Flores could very well also be the “poster child” for hitters who consistently pull the ball in the air at exit velocities between 95–105 MPH. Over his past three seasons with San Francisco, Flores has produced an Opt_95 of greater than 17% and has outproduced his xwOBA in each of the past three seasons.
Given the consistent ability that Flores has shown to maintain a high Opt_95, I would project him to be a safe bet to hit 20 home runs a season moving forward despite what his batted ball metrics suggest. As long as Flores is able to consistently pull the ball in the air at such a high rate, it is reasonable to expect that he will be able to maintain this level of power production heading into the 2024 season.
Richie Palacios + Jonny DeLuca (OF — Tampa Bay Rays):
Richie Palacios and Jonny DeLuca, two players that the Tampa Bay Rays acquired in trades over the offseason, both possess intriguing batted ball traits that indicate that they may be able to outperform their expected statistics if given enough playing time in 2024.
It should be noted that both players had small sample sizes at the Major League level last season, with DeLuca only having 45 plate appearances and Palacios only having 102 plate appearances. DeLuca has had a substantial history of pulling the ball at the Minor League level, producing a 61.5% Pull Rate at AA and a 50.8% Pull Rate at AAA in 2023. While these Pull Rates are quite extreme and are probably not optimal at the Major League level, it indicates to me that DeLuca will have no problem producing plus power at the Major League level moving forward despite having a Max. EV of 110.2 and Hard Hit Rate below 33% between AAA and MLB combined in 2023.
Personally, I am more intrigued by Richie Palacios potential moving forward as he produced a larger Major League sample size in 2023. Palacios was not a big time pull hitter throughout his time in the Minor Leagues, only achieving a Pull Rate of greater than 40% once since 2021. Upon arriving at the Majors in 2023, Palacios began to pull the ball more which caused him to produce a high Opt_95 and the greatest power output of his professional career. Was this due to an approach change or simply random variance due to a sample size of 84 batted ball events? That is a question that only Palacios can answer but I would expect Tampa Bay to encourage Palacios to lean into this pulled fly ball approach due to the fact it allowed him to produce career-high power at the back end of 2023. If Palacios is able to maintain this level of pulling the ball in the air in 2024, then we may be looking at an instance of another outfielder improving their performance with Tampa Bay after being traded by the St. Louis Cardinals, a la Randy Arozerena.
Alex Call (OF — Washington Nationals):
One player that I believe can improve their Opt_95 in order to hit for more power and improve their offensive production is Alex Call of the Washington Nationals. Making his Major League debut with the Cleveland Guardians at age 27 with the Cleveland Guardians in 2022 before being claimed off waivers by Washington that August, Call has provided the Nationals with excellent defense and plate discipline while producing at a below-average level offensively. With an adjustment to his approach at the plate, Call may be able to tap into more power and raise his level of offensive production moving forward.
As shown by the tables above, Alex Call has displayed tremendous bat-to-ball and plate discipline abilities in 2023, with a 6.8% SwStr and 22.6% O-Swing, which indicates to me that he has a plus understanding of the strike zone and would be comfortably with making adjustments to his offensive approach. swRV+, Down on the Farm’s Swing Decision metric (link at the end of the article), indicates that Call’s plate discipline was 10% better than league average in 2023, another good indicator of his feel for the strike zone when at the plate. One element that is holding back his level of offensive production is his underperformance of his expected statistics on fly balls, which can potentially be explained by his Opt_95 of 7.3%. In order to get over the 10% threshold, Call should adjust his offensive approach to pulling his batted balls in the air in order to fully tap into his power and raise his level of offensive production.
As shown by the heat maps above, one way that Call can achieve this objective is to adjust his offensive approach on Four Seamers. With the exception of a very small “cold zone” upstairs, Call is very good at making contact on Four Seamers throughout the strike zone however he tends to focus on mostly swinging at Four Seamers when they are located over the middle of the plate. While I am not going to complain about a hitter swinging at Fastballs located middle-middle, I do believe that Call should be more aggressive at swinging at Four Seamers located up-and-in, in order to make contact with the ball in front and hit more batted balls in the air to the pull side. These Swing% and Contact% heat maps remind me quite a bit of Isaac Paredes, and from a scouting standpoint it is easy to see similarities in their swings as well.
Call Video Link — Paredes Video Link
If Call is able to focus on pulling more balls in the air next season and get over the 10% Opt_95 threshold, then it is possible that he will be able to improve his level of offensive production to above league-average next season. With his combination of outstanding defense in Center Field and potential ability to improve offensively, Alex Call could be an intriguing trade candidate for contenders at the trade deadline next season.
Bryson Stott (2B — Philadelphia Phillies)
Another player that I believe can improve their Opt_95 in order to hit for more power and improve their offensive production is Bryson Stott of the Philadelphia Phillies. Since making his Major League debut in 2022, Stott has combined his bat-to-ball skills with excellent defense in order to become a valuable member of the Phillies starting lineup. If Stott is able to tap into more of his power, he can potentially become a star and an annual 30–30 threat.
As shown by the tables above, Stott showed excellent bat-to-ball skills this past season with the Phillies, producing only a 6.0% SwStr. While he was able to outperform statistics on fly balls, his 7.9% Opt_95 was below the optimal range of over 10% in order to outperform these expected statistics with consistency. While his SwRV+ and O-Swing% indicate that Stott has league-average plate discipline at best, I believe there is one particular adjustment that Stott can make in order to more frequently pull the ball in the air and unlock some untapped power.
Similar to Alex Call, I believe that Bryson Stott would have more success in hitting pulled fly balls if he was more aggressive at swinging at Four Seamers on the inner-third. As shown by the heat maps above, Stott does swing at inner-third Four Seamers but at a frequency of no greater than 70% of the time. I would be curious to see what his results would look like if he started swinging at these pitches around 80% of the time, and if this adjustment would allow for him to make contact on more pitches out in front of the plate. Taking his home ballpark into account as well, would it be possible for Stott to double his annual home run output if he is able to make this adjustment successfully? Combined with his stolen base ability, this would place Stott into 30–30 territory and turn him into one of the best second basemen in the league. Given the high potential that this adjustment could unlock, I would highly recommend that Bryson Stott adjust his approach to focus on pulling the ball in the air moving forward.
Maikel Garcia (3B — Kansas City Royals):
The final player that I believe can improve their Opt_95 in order to hit for more power and improve their offensive production is Maikel Garcia of the Kansas City Royals. Since making his Major League debut at the end of the 2022 season, has provided the Royals with outstanding plate discipline and excellent defense at third base next to Bobby Witt Jr. Garcia has displayed an ability to frequently hit batted balls with an exit velocity between 95–105 MPH, but has shown an inability to pull these balls in the air which has placed a damper on his overall offensive production.
As shown by the tables above, Maikel Garcia displayed excellent plate discipline last season, producing a 109.7 swRV+ and a 24.4% O-Swing. Garcia also exhibited plus bat-to-ball skills, producing a 7.7% SwStr. Despite producing a Hard Hit Rate of 50.6% (42.5% of which were hit between 95–105 MPH exit velocity), Garcia generated an Opt_95 of only 1.3%, which likely contributed to his abysmal .199 wOBAcon on fly balls in 2023. In my opinion, increasing the frequency of pulled fly balls would be the best way for Garcia to improve his offensive production moving forward.
Similar to Alex Call and Bryson Stott, I would recommend that Maikel Garcia swing at Four Seamers located on the inner third more often in the future, however I believe that a swing change may also be necessary in order for Garcia to reach his full offensive potential. Throughout his time in the Minor Leagues, Garcia has consistently produced high Ground Ball Rates and Fly Ball Rates lower than 35%. While his ability to hit the ball hard has allowed for Garcia to maintain high BABIP’s at each level of his professional career, he has only produced an ISO higher than .118 once.
Causes of his swing path inefficiency can be debated, however it is imperative that Garcia develops an ability to lift the ball with consistency if he wants to be able to tap into his power, improve his Opt_95, and reach his offensive potential. A detailed breakdown of his swing might be an article for another day, but it appears to me that altering the “inverse Bregman” movement with his hands at load might be a good start.
Playing in a large ballpark such as Kauffman Stadium puts him at a slight disadvantage, but Garcia’s tools are so good that it would be a mistake in my opinion to not place a focus on improving his swing to be more conducive to power. If Garcia is able to pull the ball in the air more and increase his output, he could become a perennial 20–20 player with plus defense and on-base ability, who would be an excellent compliment with Bobby Witt Jr. on the left side of the infield for many years to come for the Kansas City Royals.
Concluding Thoughts:
Being able to identify undervalued players who have particular traits that can be further developed is one main component of running a successful Major League Baseball organization, and the creation of Opt_95 allows us on the public side to better evaluate how hitters may overperform their expected statistics. Hitting the ball hard and in the air is always good, however it is imperative that hitters who frequently hit batted balls between 95–100 MPH to pull the ball in the air because this is where they will achieve the greatest success. By creating a statistic that is able to evaluate this ability, we are able to better identify players who can improve their power output in the future despite surface-level batted ball metrics that may suggest otherwise.
While I would like for the R-squared values to be higher, I do believe that Opt_95 is a good measure for analyzing if a player can sustain overperforming their xwOBAcon on fly balls. I am curious to see if incorporating features such as hitter’s average exit velocity and launch angle within the 95–105 MPH exit velocity range would improve the predictive abilities, and this will be a point of research moving forward. In conclusion, Opt_95 offers a more refined lens through which we can evaluate and project a hitter’s potential by meticulously dissecting the subtleties of spray angles and exit velocities in order to identify players who can outperform their expected statistics on a consistent basis.
Follow @MLBDailyStats_ on X (Twitter) and Adam Salorio on Medium for more in-depth MLB analysis. Data from Baseball Savant, FanGraphs, and Down on the Farm.
Photo Credits to Tampa Bay Times, Associated Press, Getty Images, Washington Nationals, and USA Today.
