MLB Insiders Are ‘Quite Concerned’ About Increase in Arm Injuries to Top Young Starting Pitchers

Matt Blake sent a conciliatory message to Cleveland Guardians pitcher Shane Bieber over the weekend. As a member of Cleveland’s player development system in the 2010s, Blake aided Bieber’s rise from college walk-on to unanimous American League Cy Young Award winner in 2020. For a time, Bieber served as the role model modern to produce a big-league ace, a player who added strength to his body, velocity to his fastball and spin to his off-speed pitches as he climbed the ranks.

By the time Blake sent his message, though, Bieber had become part of a growing and increasingly worrisome demographic: talented young pitchers who will spend this season as spectators. Two days after the Miami Marlins announced that 20-year-old phenom Eury Pérez would undergo Tommy John surgery, the Guardians revealed that Bieber, 28, would need the same procedure. A recent exam of 25-year-old Atlanta Braves starter Spencer Strider revealed damage to the ulnar collateral ligament in his elbow, which could result in his second Tommy John surgery. In New York, where Blake is now the Yankees’ pitching coach, the team lost its ace, Gerrit Cole, to elbow inflammation until June and one of its top relievers, Jonathan Loaisiga, to an End of year elbow surgery.

“As a pitching coach trying to get through nine innings of pitching every night in 162 games,” Blake said, “I’m pretty concerned.”

Throwing has always been dangerous for its practitioners. There is reason to believe that keeping them healthy is becoming increasingly difficult. The opening days of the 2024 season demonstrated the inherent fragility of the position. A recent story by The Ringtone cited research by former MLB manager Stan Conte that recorded 263 UCL surgeries in 2023, a steady increase from 111 procedures performed in 2011. Of the 166 players who began the season on the injured list, as the New York Post reported, 132 were pitchers. If these trends continue, 2024 will be another banner year for arm injuries and will raise alarm in the game.

The topic sparked controversy between Major League Baseball and the MLBPA on Saturday, as the two sides argued through press releases over the effect of the pitch clock, which was introduced in 2023 and shortened for 2024. MLBPA chief Tony Clark painted the league’s insistence on cutting free time ahead of the 2024 season against players’ wishes as “an unprecedented threat to our game.” MLB countered by citing unpublished analysis from Johns Hopkins University that found no link between the introduction of the clock and the onset of injuries.

The clock, however, was just one point of concern among the players, coaches and executives interviewed Atletico this weekend. Those conversations presented a number of additional reasons for the injury problem, including the industry’s relentless push for optimization, the encouragement of players to pursue maximum speed and rotation, and the use of training methods that encourage workouts at full throttle all year round. For some, the explanations are intertwined and intractable. Untangling the knot may require years of research and reevaluation.

“Protecting these guys’ arms is critical,” Dodgers manager Dave Roberts said. “And we clearly didn’t nail it.”

This season began with baseball’s most heralded pitchers on the shelves. Los Angeles Dodgers starter Clayton Kershaw underwent shoulder surgery last October. Texas Rangers pitcher Max Scherzer is recovering from back surgery, while his teammate Jacob deGrom is rehabbing from a second Tommy John surgery. Houston Astros ace Justin Verlander felt shoulder pain during spring training. All those pitchers are 35 or older, the kind of age when the body no longer cooperates with the rigors of the big league schedule.


Not long ago, Eury Pérez and Sandy Alcántara were on their way to becoming twin aces for the Marlins. Now both will spend 2024 rehabilitating after surgery. (Megan Briggs/Getty Images)

For MLB, the most pressing concern is that the gun fleet will break down soon after hitting the headlines. Miami Marlins starter Sandy Alcántara, the 2022 unanimous National League Cy Young Award winner, underwent elbow reconstruction last season. Tampa Bay Rays pitcher Shane McClanahan did the same, just over a year after starting the All-Star Game. Milwaukee Brewers pitcher Brandon Woodruff will miss this season due to shoulder surgery. Same story for Kansas City Royals pitcher Kyle Wright, a 21-game winner with Atlanta in 2022.

“Our sport deserves to have our best pitchers on the mound,” Detroit Tigers manager AJ Hinch said. “No matter what era you’re in, the starting pitchers’ matchup is the first thing you watch every day. You want the big guys to be out there. You want the elite guys, and more and more they get hurt.

To investigate the issue, MLB commissioned a study last October, which expanded to include conversations with 100 people about the game, including medical officials. Once the study is complete, the league plans to create a task force and provide recommendations to clubs on how to keep pitchers healthy.

The sport has faced the problem since its inception. In another era, it was believed that pitchers got hurt from overuse. Teams changed how they used pitchers in hopes of preserving them. Gone are the days when the exhausted starter, pushed to the limit after 125 pitches or more, tried to finish the seventh or eighth inning. The new archetype asks the pitcher not to loosen the releases but to explode at the start. Go as hard as you can for as long as you can, is the new mantra. An influx of data on the shape and movement of pitches has given teams granular ways to improve pitchers. The data, however, did not offer an answer for how to keep them healthy.

“I’ve heard in my years of management that we ask less of starting pitchers because we don’t leave them in the game long enough and they don’t throw 100 pitches anymore,” Hinch said. “Yet we ask them for maximum speed, maximum form, maximum everything and to train virtually all year round.”

Hinch pointed to Tarik Skubal, a 27-year-old Tigers lefty who underwent Tommy John surgery in college and flexor tendon surgery in 2022. Skubal trained last winter so that when he came to practice spring, hit 99 mph in his first live batting practice session. “You go to Tarik Skubal and say, ‘Hey, take the pressure off and throw 92 mph,’ and see how that works for you,” Hinch said. “NO. Because we ask our athletes to compete at the highest levels.”

For some retired players, the pursuit of speed and spin has put pitchers at risk. Dan Haren, a 13-year veteran who now works as a pitching strategist for the Arizona Diamondbacks, posted on on his Instagram feed which provides footage of “boys throwing weighted balls at maximum effort against a wall, with a crow leap, with his brothers cheering him on.” Roberts added: “The body is designed, in my opinion, to only withstand a certain amount of force and speed before giving out.”


Shane Bieber had not been allowed to race for two outings this season when it was announced he would undergo elbow surgery. (Jason Miller/Getty Images)

Some, like Chicago Cubs manager Craig Counsell, have suggested that pitchers will always try to throw harder. “I don’t think the pursuit of speed will ever end,” Counsell said. “Because it’s something that makes pitchers better. “I don’t think we should demonize the pursuit of speed.”

Yet the industry has supported this trend by shortening rookie pitchers’ outings and encouraging them to maximize their production. Not only do pitchers throw their fastballs as hard as possible, but they throw offspeed pitches with maximum force, in hopes of generating unique swings and missing bats. “The types of deliveries that create abnormal shapes are probably more stressful in some way,” Blake said. “I think maximizing force to create shapes probably doesn’t help. When you’re chasing 20-inch pause or 20-inch run or the high velo, I think there’s a certain level of physical toll.

Despite protests from MLB officials, players will continue to complain about the clock. The innovation reduced the average of last season’s games by 24 minutes. The clock in 2023 gave pitchers 15 seconds to act with the bases empty and 20 with runners on. MLB’s 11-man competition committee voted to shave two seconds off the 20-second clock for 2024, despite objections from players.

Los Angeles Angels pitcher Tyler Anderson suggested that pitchers might put more stress on their arm than their legs because of the clock. But he doubted any study could show a correlation between decreased time between shots and increased injuries. The act of throwing was already unhealthy enough. “Rob Manfred knows that’s really hard to prove, I guess,” Anderson said.

The union sees the clock as a bogeyman. The commissioner’s office sees their complaint as a straw man. For coaches like Blake, who must navigate the season as injuries continue, the clock is only part of the problem, along with the dangerous pursuit of speed and rotation.

“I don’t think any of them are the most responsible,” Blake said. “But their cocktail is hard to top.”

Atletico’s Fabian Ardaya, Sam Blum, Patrick Mooney, Cody Stavenhagen contributed reporting.

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(Top photo by Strider: Justin K. Aller/Getty Images)