In the 1960s and 1970s, American psychiatrist Aaron Beck (1921-2021) developed a new kind of psychotherapy, which, as he saw it, would help patients deal with depression. At the core of Beck’s analysis was the idea that how people think affects how they function. Beck reasoned that, since the goal of therapy is to improve the lives of patients, the cultivation of better mental habits is essential to that end.
In time, Beck’s approach would evolve into what is now called cognitive behavioral therapy (CBT). But his insights were by no means confined to doctors’ offices and mental health retreats. Drawing on the psychological insights of Lionel Rosen and Spencer Johnson, plus the motivational acumen of Jon Gordon, legendary football coach Nick Saban developed a coaching and playing philosophy that he liked to call “The Process.” According to Saban, optimal athletic performance depends on an optimal mental approach. Too many athletes worry about the ends when it’s the means that matter. Sure, a running back may explode for a random 100-yard game, or a hitter may swat three homers in his first week of pro baseball, but long-term success is process-driven. Consistency beats hype; discipline trumps flash. An athlete who, whatever the external circumstances, is relentlessly focused on executing a given task in accordance with a fixed standard is the best bet in the long run. Athletic excellence lies in good habits, not capricious results.
For Saban, “The Process” largely concerns how a given athlete prepares for, and thinks about, the next play. It is associated with one’s mental approach to the task at hand. Yet, isn’t the same thing often said of hitting? Coaches implore hitters to “have an approach.” Scouts praise a prospect because he has a “great approach.” In other words, people in and around the game not only assume that hitters need a process in order to be the best they can be, they actively encourage it. The question is: Can this core baseball insight be rendered in a quantifiable and applicable form?
Any such rendering, doubtless, would be a proxy for the multitude of decisions that hitters must make when they step into the batter’s box. It’s not comprehensive, then, but I want to offer plate-discipline ratio (PDR) as a metric that combines two hitter-controlled outcomes (walk rate and strikeout rate) into an explanatory variable that facilitates the assessment of hitting performance and allows us to predict future success at the plate. This is a normalized ratio insofar as it compares two rates in order to shed light on a hitter’s process. PDR is not just summarizing how often a hitter strikes out or walks; it compares strikeout rate and walk rate so as to yield a statistical snapshot of the hitter’s discipline, swing decisions, and contact sustainability. In other words, while mathematically equivalent to BB/K, PDR conceptually reframes the relationship in terms of underlying plate-appearance tendencies.
To begin with, it’s important to establish how PDR works. The basic formula is as follows:
PDR = BB%/K%
In other words, PDR takes a hitter’s walk rate and divides it by his strikeout rate. Again, these are hitter-controlled outcomes compressed into a single metric. The walk rate reflects a player’s swing decisions, including his understanding of the strike zone and, in turn, his refusal to chase outside of it. The strikeout rate reflects a player’s bat-to-ball skills. Set in relationship, they indicate the stability of a player’s process or approach. PDR does not yield a merely descriptive number, telling us what so-and-so did. It gives us an accurate picture of the player’s behavioral structure and, as such, should accurately anticipate future outcomes.
Using PDR, we might group hitters under the following categories:
- Komodo Dragons: Players in this category feature high strikeout rates and low walk rates. They are overaggressive, even reckless, and can’t be counted on for sustained success. An interesting example of this type of player would be Pittsburgh Pirates outfielder Oneil Cruz. Yes, he hits the ball very hard, but there’s a reason why he has never blossomed into a star. His PDR is a mess. In 2o25, it was a poor .369 (11.8%/32%). So far in 2026, it’s an unsightly .228 (7.7%/33.7%). As of this writing, Cruz’s numbers haven’t tanked in 2026 due to a .361 BABIP — almost 100 points higher than 2025 — but PDR suggests that regression is inevitable.
- Rabbits: Players in this category feature low strikeout rates and low walk rates. They prioritize contact over everything else. Hitters of this mindset are less and less common today, though, according to PDR, they have an approach that successfully utilizes their skillset. A player such as the San Francisco Giants‘ Luis Arraez currently boasts an elite PDR of 1.29 (5.3%/4.1%), as does the Chicago Cubs‘ Nico Hoerner’s 1.14 PDR (9%/7.9%). Notably, the Cubs recently signed Hoerner to a significant, long-term contract, indicating that their front office sees in Hoerner what PDR indicates — an extremely valuable player. Notably, there are some players who ostensibly fit this mold but who, on closer inspection, fall short of high-caliber Rabbits. Take the Philadelphia Phillies‘ Alec Bohm, whose 2025 walk rate (5.8%) is similar to Arraez and Hoerner but whose strikeout rate (16.3%) does not compare favorably. With a PDR of .356, Bohm is almost a Komodo in Rabbit’s clothing.
- Lions: Players in this category feature high (or, at least, relatively high) strikeout rates along with high walk rates. They are methodical, running deep counts and looking for pitches to drive. Most of the game’s best sluggers fall into this category. In 2025, Bryce Harper had a PDR of .579 (12.1%/20.9%), Aaron Judge had a .775 PDR (18.3%/23.6%), Shohei Ohtani had a .584 PDR (15%/25.7%), Kyle Schwarber had a .548 PDR (14.9%/27.2%), and Juan Soto had a .927 PDR (17.8%/19.2%). It’s interesting to note that Harper’s PDR has climbed to .800 in 2026, thereby coinciding with his supposed return to “elite” status. However, it should be underlined that yours truly argued back in February that Harper was actually pretty elite in 2025 and due for positive regression. In point of fact, Harper’s PDR improved in 2025 (it was .548 in 2024), which boded well for his much-ballyhooed return to form in 2026.
Based on these (and other) findings, it’s reasonable to posit the following PDR thresholds:
- Elite: > .750
- Good: .500-.750
- Average: .400-.500
- Fragile or concerning: < .400
Let’s see how this stacks up with a handful of 2025 results. Among qualified hitters, here are the MLB leaders in wRC+ in 2025, along with their PDR in parentheses.
- Aaron Judge: 204 (.775)
- Shohei Ohtani: 172 (.584)
- George Springer: 167 (.624)
- Cal Raleigh: 161 (.517)
- Juan Soto: 156 (.927)
Apart from the fact that all of these players are All-Stars, one name that sticks out here is Cal Raleigh. As is well known, the Big Dumper had a breakout season in 2025 but has struggled mightily so far in 2026. PDR can help explain this retrogression. For one thing, it’s clear that Raleigh already had the shakiest approach in the above list of wRC+ leaders. Now what would happen if his PDR plummeted? Well, now we know. In 2026, his PDR is a Komodo-esque .314 (9.%/31.5%)! If Raleigh is going to return to last season’s success, his process will have to improve greatly.
Of course, like any metric, PDR has its limitations. Strictly speaking, it doesn’t take small sample sizes into consideration, so while it may augur the pending floor (or ceiling) of a young player, it’s best applied to players with a sample size of at least 50 at-bats — and ideally more. It also has to be stressed that PDR measures the soundness and viability of a hitter’s approach, not his productivity as such. Put differently, I’m not saying that Arraez is better than Judge or Schwarber! After all, if we take Schwarber’s good (not elite) PDR and combine it with his top-tier slugging percentage (.563 in 2025 vs. Arraez’s .392 slugging percentage in 2025), we get a fuller picture of his (and Arraez’s) value. What I am arguing, however, is that both Arraez and Schwarber have dependable processes that suit their skillsets and that, until something significantly changes (age, injury, etc.), they can both be counted on to contribute at the plate. Indeed, in light of Schwarber’s massive free-agent deal with the Phillies in December 2025 and Hoerner’s recent signing with the Cubs, it may be that three-time batting champion Arraez has been undervalued as a player, particularly now that his defense has drastically improved with the Giants.
Still, it cannot be denied that Arraez is a rare but useful hitter. Perhaps more young players ought to emulate him, though, given the quality of pitching in today’s game, that’s not an easy path. The most likely scenario for such hitters is that they will get Bohm-boozled, pairing low walk rates with mediocre strikeout rates. Meanwhile, as a recent article in The Athletic points out, batting averages continued to decline in MLB, even with the 2023 banning of the infield shift. Clearly, then, players like Schwarber represent the future of hitting, and it is here that PDR can make a real difference in terms of player evaluation. Imagine two hitters, each with 100 plate appearances: both have plus-plus power, and both strike out at a significant clip. So, how do you decide which player is a viable long-term asset and which is expendable? The answer is PDR. If Player A has a slugging percentage of .542 but a PDR of .147, then his success is simply unsustainable. Sure, he’s run into a few balls, but his process is broken. If he doesn’t show improvement soon, he’s an excellent candidate to sell high while his power numbers still give the illusion of success. On the other hand, Player B has a slugging percentage of .479 but a PDR of .605. He’s the keeper. Sure, his power numbers don’t (yet) equal those of Player A, but he can be counted on to continue hitting well. There’s a foundational process underlying his present accomplishments and, just as importantly, paving the way for future success.
Nick Saban was fond of saying, “There are two pains in life. There is the pain of discipline and the pain of disappointment. If you can handle the pain of discipline, then you’ll never have to deal with the pain of disappointment.” Well, baseball is a game of failure, and even the very best hitters have to face disappointment on many occasions. Still, Saban’s words hint at the core insight of what I have called plate-discipline ratio (PDR). If a hitter wants to excel at his craft, he has no choice but to pass through the crucible of discipline. It’s not easy, but, as Saban observes, there’s ultimately no other good alternative.
