Major League Baseball should consider rule changes to address the declines in pitchers’ health and the aesthetics of the game, according to an MLB internal report issued after a year-long investigation into the pitching injury epidemic.
The 63-page report was sent this afternoon from the Office of the Commissioner to MLB general managers, assistant general managers, farm directors, domestic and international scouting directors and club medical and performance staff. Sports Illustrated obtained a copy of that report, which the authors characterized as “an important first step in a longer process to identify the root causes of pitcher injuries and effective solutions to address this serious concern for the game.”
MLB in the report said it interviewed “over 200 matter experts, including former professional pitchers, orthopedic surgeons, athletic trainers, Club officials, biomechanists, player agents, amateur baseball stakeholders, and other experts in pitcher development.” It did not mention current players. The work began in fall 2023.
The report provides voices and data to what already is widely known to be a robust but costly pitching environment. Pitchers throw harder and less often, sending the strikeout rate up and batting average down, but they break down more often. The craft of pitching has been replaced with brute force and maximum effort done in short bursts, an escalating model that is blowing out elbows and shoulders.
One of the “recommended solutions” in the report is to mandate change through rules and roster limitations. The report notes that the conventional wisdom of fewer pitches and more rest may be backfiring on clubs because it encourages pitchers to throw every pitch at max effort.
“We recommend considering rule changes at the professional level that shift the incentives for Clubs and pitchers to prioritize health and longevity,” the report said.
It advises a new world in which “pitchers are encouraged or required to moderate their activity and throw at sub-maximum effort to go deeper into games may be better for pitcher health … For instance, playing rules could be adjusted or designed to encourage or require starting pitchers to preserve enough energy to allow them to pitch deeper into games. These incentives could be supported by roster rules that more appropriately regulate the availability of pitchers on a roster or in a team’s bullpen for a given game, including potential changes to the number and frequency of transactions that allow Clubs to replace pitchers on their rosters.”
The recommendation is in line with previous internal and preliminary discussions MLB has had about a minimum innings requirement per game for starters, a penalty for removing a starter before a certain inning threshold and a reduction in pitchers that can be carried on the active roster.
According to data in the report, the days pitchers spend on the injured list has more than doubled since 2015, passing 30,000 days this year. Tommy John surgeries for major and minor league pitchers has increased 69% since 2015, reaching 281 last season—or one for every day of the championship season.
The modern style of pitching, the report said, detracts from the quality and attractiveness of the game. Pitcher health, it said, “directly impacts fan engagement. Pitcher injury rates and the associated risk factors (like max-effort pitching) go hand in hand with the modern style of play, including the rise of strikeout-oriented pitching, the decline in prominence of the starting pitcher, and the regular churn of players on and off the roster, none of which are fan friendly.”
Among its many findings, the report also addressed:
The cost of velocity
The report characterized velocity as being at the root of the problem. It drives the amateur market and scouting, not just professional performance, at a high cost.
“The industry experts we spoke to concurred with the medical research,” the report said, “and overwhelmingly identified velocity as the primary factor leading to the increase in pitcher injuries. As velocity increases, torque on the elbow also increases.”
The technology-driven chasing of spin and pitch characteristics
The emphasis on pure “stuff” over the craft of pitching in pitching labs and independent training centers has heightened injury risk, many experts said.
In its most sweeping summation of why so many pitchers are breaking down, the report said, “[W]e conclude that although the potential contributors are complex and many factors are still unknown, the most significant causes are likely the increased velocity of pitches, the emphasis on optimizing “stuff” (a term referencing the composite movement characteristics of pitches, including horizontal and vertical break and spin rate), and the modern pitcher’s focus on exerting maximum effort while pitching in both game and non-game situations.”
March is the most dangerous month for pitchers
From 2017 to 2024, the placement of pitchers on the injured list from spring training to Opening Day soared 82%. But the rate once the season started increased only 17%, including a decline in each of the past three years.
The medical experts interviewed “agreed that offseason interventions, particularly those focused on max effort throwing or the pursuit of rapid increases in velocity, are more likely to result in increased injury risk.”
Data confirms the widespread adoption of “max effort”
From 2017 to 2024, the standard deviation of four-seam fastball velocity declined from 1.18 to 1.09. That means there is less modulation going on as pitchers get closer to throwing every fastball as hard as they can.
Clubs are contributing to this “max effort” style by asking their pitchers to throw fewer innings and pitches. The standard deviation sunk to its lowest in 2020 (1.04) when, in a 60-game season after an abbreviated spring training and with expanded rosters, pitchers threw even shorter outings.
The types of injuries are changing
The increased velocity and the extreme pitch-shaping that pitchers chase—such as “ride” for four-seamers and horizontal break for power breaking pitches, especially the sweeper—creates shoulder injuries at rates and kinds not seen before. Orthopedists quoted believe the extreme manipulation of the baseball—including grip pressure, pronation and supination, and the max effort required in practice to achieve the desired result—may be to blame.
Said one surgeon: “It’s causing this what we call eccentric load on muscles on the inner side of the elbow and then everywhere up the kinetic chain, meaning the lat and teres, which we’re seeing a huge number of tears in now that we hadn’t seen before, plus shoulder capsular tears. So, I think they are all a consequence of this change in pitch design.”
Said another: “When you look at the shoulder, you see more lat teres major, subscap, capsule injuries—I’ve seen more in the last 5 years than I saw in the prior 25. … The capsule’s under maximum violent stretch and those muscles are the exact ones that would be trying to protect the capsule at that instance. This is just an estimate, but it used to be 80 percent to 20 percent chronic to acute, now it’s maybe flipped. Some of the injuries are absurd. Sub-scap tears, lat tears, rib fractures . . . you know how hard it is to fracture a rib throwing a baseball? Now you have a lat that’s ripping off the bone. Part of that, the younger kids have more mileage, but also it’s the aggressiveness.”
Minor league development may also be at fault
Clubs treat minor league pitchers even more conservatively with their workloads, which encourages max effort pitching and does not build endurance. According to the report: “Club representatives noted that certain workload management practices, which are intended to keep players healthy, may have unintended effects on player health. In this respect, there is a perceived trend of Minor League players being underprepared to handle Major League workloads.”
Player incentives
Pitchers chase velocity and nasty spin because the methods get results, both in performance and salary. Clubs encourage it with their usage patterns. And pitchers determine those incentives are greater than the risks.
“Pitchers are willing to train in a manner that exposes themselves to injury because that style of pitching is economically rewarded, both for the league’s best players and for players trying to establish themselves,” the report said.
It’s the conundrum baseball faces: How do you change behavior when the incentives fuel the system?
The same issues plague amateur baseball
The report finds, “In amateur baseball, younger pitchers have similarly adopted the pursuit of velocity, ‘stuff,’ and a max-effort style of pitching and training, even though these practices may be inappropriate at such young ages.”
The report noted that from 2014–19, an average of 5.6 pitchers per year threw at least 95 mph at the National Perfect Game showcase, which features top high school players. The number of elite high school throwers has gone up every year since. This year there were 36 pitchers who reached at least 95 mph.
Said one orthopedic surgeon in the report: “The velocity keeps going up, guys are getting bigger and stronger—as they keep getting stronger, their ligament doesn’t necessarily get stronger. I see a lot of kids, most people do—some kids rip the bone off their elbow because their growth plate is weaker than the ligament. Instead of the ligament failing, the bone breaks off. That used to happen occasionally, but now it’s happening more and more.”
Change in the amateur market is difficult. As the report acknowledges, “Because amateur players will generally strive to model their own behavior after professional players, training and development practices in the Major Leagues and Minor Leagues will need to be adjusted before meaningful change at the amateur level will be possible.”
The pitch clock
The report found, “Current data has not demonstrated a correlation between the introduction of the pitch clock and injury risk.” It recommended further study.
The current pitching model harms the quality of the game
“Finally,” the report said, “we note that the primary injury factors – the focus on velocity, ‘stuff,’ and max-effort pitching – have caused a noticeable and detrimental impact on the quality of the game on the field. Current pitching practices are focused on the prevention of run-scoring through the accumulation of strikeouts; such trends are inherently counter to contact-oriented approaches that create more balls in play and result in the type of on-field action that fans want to see. The prominence of the starting pitcher has diminished as modern pitchers have developed to throw harder over shorter stints.”
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This article was originally published on www.si.com as MLB Internal Report Suggests New Pitching Rules to Curtail Injuries, Make Game More Entertaining.
