One of the defining storylines of Spring Training and the first couple weeks of the MLB regular season has been the prevalence of significant injuries to key pitchers. 

While that is a concern every year — particularly early in the schedule as players build their arms back up — the number of big names suffering arm injuries led the league and Players Association to trade barbs over the weekend.

On Saturday, the players union put out a brief statement on X that implied the pitch clock was a key contributing factor:

“Despite unanimous player opposition and significant concerns regarding health and safety, the commissioner’s office reduced the length of the pitch clock last December, just one season removed from imposing the most significant rule change in decades,” MLBPA executive director Tony Clark said. “Since then, our concerns about the health impacts of reduced recovery time have only intensified. The league’s unwillingness thus far to acknowledge or study the effects of these profound changes is an unprecedented threat to our game and its most valuable asset — the players.”

This is the second season in which the pitch clock has been in use at the major league level. In 2023, pitchers had 15 seconds between pitches when no runner was on base and 20 seconds to begin their delivery with runners aboard. 

Over the winter, the competition committee passed a rule change cutting the latter time from 20 to 18 seconds. That measure was approved by the six league representatives on the rule committee; all four players on the panel voted against it. 

The MLBPA released a statement at the time calling the changes “unnecessary” and saying the 2024 season “should be used to gather additional data and fully examine the health, safety and injury impacts of reduced recovery time.”

MLB quickly fired back after Clark’s latest statement. The league argued that there has been no empirical backing pointing to the clock as a contributing factor to pitcher injuries. MLB instead suggested the main issue is the increased stress which pitchers are putting on their arms to improve the quality of their arsenals.

“(The MLBPA’s) statement ignores the empirical evidence and much more significant long-term trend, over multiple decades, of velocity and spin increases that are highly correlated with arm injuries,” the league said in a statement of its own. “Nobody wants to see pitchers get hurt in this game, which is why MLB is currently undergoing a significant comprehensive research study into the causes of this long-term increase, interviewing prominent medical experts across baseball which to date has been consistent with an independent analysis by Johns Hopkins University that found no evidence to support that the introduction of the pitch clock has increased injuries.

The league said in the statement that Johns Hopkins “found no evidence that pitchers who worked quickly in 2023 were more likely to sustain an injury than those who worked less quickly on average.”

It added that, “JHU also found no evidence that pitchers who sped up their pace were more likely to sustain an injury than those who did not.”

Concerns about pitcher health are an annual event, although there hasn’t been much consensus about which factors are more responsible than others. 

Last month, noted orthopedic surgeon Dr. Keith Meister told Ken Rosenthal and Eno Sarris of The Athletic that he considered the sweeping breaking ball and power changeup to be problems, pointing to the tighter grip that pitchers use on those offerings. A few players and other injury experts pushed back against Meister’s hypothesis, arguing that increased effort to maximize velocity (on both the fastball and breaking stuff) was the more notable driver.

Whatever the case, there’s no doubt that pitcher injuries have been a major story in recent weeks. 

Gerrit Cole (elbow inflammation), Lucas Giolito (internal brace surgery), Eduardo Rodriguez (lat strain), Anthony DeSclafani (flexor tendon surgery) and Trevor Stephan (Tommy John surgery) were among the pitchers to suffer notable injuries during Spring Training. Giolito, DeSclafani and Stephan underwent season-ending surgery before Opening Day.

Since the season began, Eury Pérez, Shane Bieber and Jonathan Loáisiga have all been lost for the year due to elbow ligament repairs of their own. Things are still up in the air for Braves ace Spencer Strider, who landed on the injured list over the weekend after imaging revealed UCL damage in his elbow.

It’s not an issue for which there are simple solutions. Justin Verlander, who has been one of the preeminent workhorses of his generation but lost the 2021 season to a Tommy John procedure, discussed the issue over the weekend. Verlander, on a minor league rehab stint to build up after a seemingly minor bout of shoulder soreness, pointed to a confluence of factors, relayed by Ari Alexander of KPRC 2.

While he noted “it would be easiest to … blame the pitch clock,” the three-time Cy Young winner spoke about pitchers’ desire to maximize their swing-and-miss acumen even if it comes with a higher chance of injury. 

Verlander pointed to the increase in home runs over the past few seasons and teams’ heavier reliance on their bullpens — which he acknowledged is supported by data indicating that relievers tend to be more effective than a starter navigating a lineup for the third or fourth time — as reasons for pitchers to avoid pitching to contact.

Team decision-makers also need to wrestle with the balance between protecting their most talented pitchers without sapping their effectiveness. That’s an inexact science for medical and coaching staffs. 

Mariners manager Scott Servais pointed to the early-season spate of injuries as a factor in pulling young righty Bryce Miller at 78 pitches after seven scoreless innings in a win over the Brewers on Saturday, according to Ryan Divish of the Seattle Times.

Servais cited a desire to minimize the amount of potentially high-stress innings that Miller faces early in the season as one of a number of variables in making what seemed to be an atypically quick call to the bullpen. 

That’s just one example, but it’s illustrative of the kind of concerns which front offices and coaching staffs face as they try to keep their best pitchers healthy.