More UCL Tears Prompt Pointed Exchange, Few Answers to Baseball’s Thorny Mess

Joe Nicholson-USA TODAY Sports

If last week’s news that Eury Pérez would need Tommy John surgery was bad, Saturday was a whole lot worse. Within a span of five hours, the baseball world learned that the Guardians’ Shane Bieber, the Yankees’ Jonathan Loáisiga, and the Braves’ Spencer Strider have all incurred significant damage to their ulnar collateral ligaments, with Bieber headed for Tommy John surgery, Loáisiga set to undergo season-ending surgery as well, and Strider headed to see Dr. Keith Meister, the orthopedic surgeon who will perform the surgeries of the other two.

The losses of those pitchers is a triple bummer, not just for them and their respective teams — each of which leads its division, incidentally — and fans, but for the sport in general. Underscoring the seriousness of the issue, by the end of Saturday both the players’ union and Major League Baseball traded volleys regarding the impact of the introduction of the pitch clock on pitcher injuries in general.

Bieber, a two-time All-Star, won the AL Cy Young award and the pitchers’ Triple Crown during the pandemic-shortened 2020 season, but missed significant time in two out of the past three years due to injuries. In 2021 he was limited to 16 starts due to a strain of his subscapularis, the largest of the four muscles that make up the rotator cuff, and last year he made just 21 starts, missing 10 weeks due to elbow inflammation. He had pitched very well this season, with a pair of scoreless six-inning outings, each totaling just 83 pitches. He struck out 11 A’s in Oakland on Opening Day and then nine Mariners (without a single walk) in Seattle on April 2.

Bieber experienced more soreness than usual while recovering from the Opening Day start, but the 29-year-old righty and the team decided to proceed without extra rest, according to’s Mandy Bell, who wrote, “Bieber wanted to see if he could push through this, considering he hadn’t felt any pain in Spring Training.”

The discomfort persisted during Bieber’s second start, after which the team ordered additional testing, “which revealed the injury to the same ligament he had problems with last year,” wrote Bell. If I’m not mistaken, that last bit of information is new, as previous reports of last year’s injury did not specify as to the inflammation’s cause. “He really put in a ton of work this winter and throughout spring training, and we all felt he was on a good path to stay healthy and contribute for the balance of the season,” said president of baseball operations Chris Antonetti on a Zoom call with reporters. Antonetti additionally lauded the pitcher’s “sheer toughness and grit” in maintaining a high level of performance, while manager Stephen Vogt sounded a similar note in saying, “The amount of work that this guy’s put in over the last few years, the things that he’s pitched through, that’s a testament to who he is.” But those supportive statements raise the question of whether this juncture could have been avoided had Bieber taken a longer time to heal from the damage found last summer, as teammate Triston McKenzie did. Missing from that comparison, however, is information regarding the severity of the two pitchers’ tears, details to which we’re not privy.

As a pending free agent, Bieber is in a tough spot, as he’ll enter the market under a cloud of uncertainty, likely cutting into a payday that’s ceiling has already been reduced by his previous outages. As for the Guardians, their remaining rotation looks so shaky that it ranks 27th in projected WAR via our Depth Charts, and their Playoff Odds have decreased since Opening Day (from 33.5% to 32%) despite the 7-2 start that has put them atop the AL Central.

The 26-year-old McKenzie, who was limited to four starts last season by a teres major strain as well as his UCL sprain, was rocked for five runs (four earned) in 3.1 innings in his first outing on Monday against the Mariners. His four-seam fastball averaged just 90.5 mph, down two miles per hour from 2022, when he was fully healthy. Carlos Carrasco, now 37, is coming off a 6.80 ERA in 20 starts with the Mets. Both Tanner Bibee, a 25-year-old righty, and Logan Allen, a 25-year-old lefty, are coming off strong rookie seasons and have pitched well in the early going, but Gavin Williams, a 24-year-old righty who posted a 3.29 ERA and 4.05 FIP in 16 starts as a rookie last year, began the year on the injured list due to elbow inflammation himself and has not yet been cleared to begin a rehab assignment. Out on rehab assignments are 25-year-old righty Xzavion Curry, and 32-year-old righty Ben Lively, both of whom were sidelined by a respiratory virus during spring training. Both split time between starting and relieving last year but turned in ERAs and FIPs over 5.00, the former with the Guardians, the latter with the Reds. Joey Cantillo, their top upper level pitching prospect, is out for 8-10 weeks with a left hamstring strain.

As for the 29-year-old Loáisiga, he’s been so beset by injuries throughout his career — including Tommy John surgery in 2016 — that he’s thrown 50 innings in a major league season just once (70.2 in 2021) and has totaled 50 innings between the majors and minors just two other times, in 2018 (80.2, mostly as a starter) and ’22 (50 exactly). He was limited to 17.2 innings last year due to in-season surgery to remove a bone spur in his elbow, then less than five weeks after returning was sidelined by inflammation in the joint. Three appearances into this season, he was diagnosed with a flexor strain and a partially torn UCL, though based upon the reporting, it sounds as though he’s a candidate for the internal brace procedure that requires less recovery time. Via’s Bryan Hoch:

Meister’s initial reading of an MRI performed on Thursday in New York suggests that Loáisiga could avoid undergoing what would be his second career Tommy John surgery, with the estimated recovery for Meister’s preferred procedure spanning 10-12 months.

It was Dr. Jeffrey Dugas who invented the internal brace procedure, in which collagen-coated FiberTape suture is used to anchor the damaged UCL, speeding up recovery by eliminating the time needed for a tendon to transform into a ligament. Meister has pioneered the combining of traditional Tommy John surgery with the use of the internal brace; when it’s referred to at all as different from traditional Tommy John, it’s as a “hybrid” procedure. It’s what Jacob deGrom had last year (with Meister performing the procedure), and it sounds like what Shohei Ohtani (who was operated on by Dr. Neal ElAttrache) underwent last fall as well. In a March 7 piece in the Dallas Morning News, Meister said he’s done over 300 hybrid surgeries since 2018, which suggests the distinctions are being blurred when we track such surgeries.

Regardless of the type of surgery, Loáisiga’s absence has dealt a significant blow to a bullpen that already looked considerably less formidable than in years past. After ranking third in the majors with 7.2 WAR in 2021 and fifth with 5.9 in ’22, the unit slipped to 16th (4.2 WAR) last year, and ranked 19th in our preseason positional power rankings; Yankees relievers are now down to 22nd. Beyond closer Clay Holmes and setup man Ian Hamilton, it’s a largely unfamiliar if not untested cast, featuring a pair of ex-Dodger southpaws (Victor González and Caleb Ferguson), a trio of righties with career ERAs above 5.00 (Nick Burdi, Dennis Santana, and Luke Weaver). Moreover, the 31-year-old Burdi has never thrown more than 8.2 innings in a major league season, and another righty, Jake Cousins, has just 55.2 career innings, 30 of which came in 2021. Maybe pitching coach Matt Blake and company can find some diamonds in the rough, and maybe the likes of Tommy Kahnle, Lou Trivino, and Scott Effross can recover from their various injuries and surgeries to provide help later this season, but this is a clear weakness for a team off to an 8-2 start.

Strider is coming off a stellar season — his first full one in the rotation — in which he led the NL in strikeouts (281), strikeout rate (36.5%), FIP (2.85), and wins (20) while making his first All-Star team and placing fourth in the Cy Young voting. After throwing five innings of two-run ball while striking out eight on Opening Day against the Phillies, he surrendered five runs in four innings against the Diamondbacks on Friday, then complained about elbow discomfort afterwards. The Braves sent the 25-year-old righty for an MRI, after which the team’s official Twitter account shared the bad news:

Strider already underwent his first Tommy John surgery as a sophomore at Clemson in 2019. While it’s not a guarantee yet that he’ll need a second one, the Braves sound resigned to it, with manager Brian Snitker telling reporters, “The good news is he’s going to get whatever it is fixed and come back and continue to have a really good career.” Strider at least has security even if he’s never the same, having already signed a six-year, $75 million extension in October 2022, the largest pre-arbitration extension ever for a pitcher.

The Braves will certainly feel his loss. Of their remaining starters, 40-year-old righty Charlie Morton has been reliable and durable, taking the ball at least 30 times in each of the past three seasons, but 30-year-old lefty Max Fried was limited to 14 starts last year by hamstring and forearm strains as well as a blister on his index finger. Lefty Chris Sale, 35, missed 10 weeks last year due to a stress fracture in his scapula, which limited him to just 20 starts — nine more than he totaled over the three prior seasons combined while missing time due to Tommy John surgery and a stress fracture in his rib. Thirty-year-old righty Reynaldo López is starting again after spending nearly all of the past two seasons as a reliever. Twenty-four-year-old righty Bryce Elder was an All-Star last season but was optioned to Triple-A Gwinnett to start the year after a second-half fade and a rough spring. Prospects AJ Smith-Shawver, a 21-year-old righty, and Dylan Dodd, a 25-year-old lefty, are also at Gwinnett; the former was no. 63 on our Top 100 Prospects list. Ian Anderson and Huascar Ynoa are both recovering from Tommy John, the former from April 2023 and the latter from September ’22. One way or another, the Braves will cobble things together, but they can’t afford too much else to go wrong.

Saturday’s flood of UCL-related headlines followed a week that featured the bad news about Pérez as well as Tommy John surgery for A’s reliever Trevor Gott. On Saturday evening, Major League Baseball Players Association executive director Tony Clark released a statement that targeted the pitch clock as the culprit for so many arm injuries:

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.

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.

The league quickly countered:

This 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. 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. In fact, JHU 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. JHU also found no evidence that pitchers who sped up their pace were more likely to sustain an injury than those who did not.

Particularly in the wake of the recent in-house drama that resulted in a challenge to his leadership of the union, Clark’s statement is probably better understood as a political one than a scientific one. The majority of the players he represents are pitchers, and they may be looking for a target for their anger and fears regarding increased injury rates. It’s worth noting that those players — or at least the major leaguers who were part of the union when the most recent Collective Bargaining Agreement was hammered out in March 2022 — agreed to the structure of the Joint Competition Committee, which contains six owners, four players, and one umpire; “unanimous” is more likely referring to those four players rather than the 6,000-plus the MLBPA now represents.

As the league’s statement notes, and as The Ringer’s Ben Lindbergh reported last week, MLB has been conducting a comprehensive study of pitcher injuries since October, and once it’s done (perhaps later this year) “intends to form a task force that will make recommendations for protecting pitchers.” The group will “try to come up with some solutions and implement some solutions,” according to Dr. Glenn Fleisig, who as the biomechanics research director at the American Sports Medicine Institute and as an injury research adviser for MLB is one of the experts being consulted.

To varying degrees, Fleisig, Meister, ElAttrache and the now-retired Dr. James Andrews have all publicly pointed to the extra stress on arms induced by the quest for increased velocity, increased spin, and maximum effort as the primary causes of increased pitcher injury rates, a quest that starts in youth baseball, while players’ bodies are still developing. Leaguewide data from the pitch-tracking era particularly points to the way major league players and teams have chased velocity:

Four-Seam and Breaking Ball Velocity and Spin
Season FF% FF Avg Velo FF Avg Spin FF% ≥ 97 BB% BB avg velo BB Spin
2008 33.8% 91.9 3.8% 22.7% 80.5
2009 35.1% 92.1 4.2% 23.7% 80.7
2010 32.9% 92.2 4.8% 23.6% 80.8
2011 33.2% 92.4 4.6% 24.8% 81.2
2012 33.6% 92.5 5.0% 25.3% 81.1
2013 34.7% 92.7 5.5% 25.2% 81.5
2014 34.2% 92.8 6.1% 24.6% 81.7
2015 35.5% 93.1 2239 8.2% 24.8% 82.2 2193
2016 35.9% 93.2 2266 8.5% 26.3% 82.1 2368
2017 34.5% 93.2 2260 8.2% 27.2% 82.0 2417
2018 35.0% 93.2 2267 7.7% 27.5% 82.2 2436
2019 35.8% 93.4 2289 8.0% 28.5% 82.4 2465
2020 34.7% 93.4 2305 8.5% 29.1% 82.2 2479
2021 35.4% 93.7 2274 9.1% 29.3% 82.6 2452
2022 33.2% 93.9 2274 11.2% 31.1% 82.8 2459
2023 32.2% 94.2 2283 12.3% 31.2% 83.0 2460
2024 31.2% 94.0 2282 11.6% 30.9% 83.0 2458
SOURCE: Baseball Savant

The average four-seam fastball velocity has consistently crept up by 0.1–0.2 mph per year, with a couple jumps of 0.3 mph; while it’s down thus far this year, velocities tend to increase once the weather warms up. The percentage of four-seamers 97 mph or higher more than tripled from 2008–23, and shot up 54% from 2019–23. The average spin rate for four-seamers increased by only about 2% from 2015 — the first year of Statcast — to ’23, and while the average spin rate for all breaking pitches combined increased by about 12% in that span, most of that jump was in the first two seasons. Those spin rates have been pretty consistent since then, but the total volume of breaking balls has increased.

The idea that the pitch clock could be contributing by making pitchers dial up to maximum intensity with less time to recover between pitches has intuitive appeal, but injury rates had already risen before the clock’s introduction last year. As Baseball Prospectus’ Derek Rhoads and Rob Mains noted, the total of 233 pitchers who landed on the injured list last year was about the same as in 2022 (226) and ’21 (243), up from ’19 (192). Likewise for the number of Tommy Johns as measured by year, starting with the day that pitchers and catchers report (as opposed to a calendar year): 28 for last season, compared to 26 for 2022, 31 for ’21, 27 for ’20, and 16 for ’19. In a study published last June, my colleague Dan Szymborski found no meaningful relationship in injury rates with regards to the pitchers whose pace increased the most from 2022 to ’23, at least to that point. The Hopkins study that MLB cited has yet to be published, though it’s hard to believe that the league hasn’t shared its preliminary findings with the union. Notably, Clark did not point to any study that produced a result that reflected his constituency’s concerns.

On the subject of velocity, the link between Strider’s high velo and the propensity for such pitchers to require Tommy John is hard to miss. Of the top 15 starting pitchers in terms of average four-seam fastball velocity from 2021–23, 10 have undergone at least one surgery to repair their UCLs, and Strider is in danger of becoming the fourth to need a second:

Highest Average Four-Seam Fastball Velocity, 2021–23
Pitcher Pitches Avg Velo (mph) TJ/UCL repair
Jacob deGrom 1385 99.0 6/12/23 (2nd)
Hunter Greene 2317 98.6 4/9/19
Sandy Alcantara 2063 98.0 10/6/23
Spencer Strider 3381 97.7 2/1/19
Grayson Rodriguez 1043 97.4
Gerrit Cole 4836 97.3
Tyler Glasnow 1575 97.4 8/4/21
Luis Castillo 3150 97.3
Shane McClanahan 2439 96.7 8/21/23 (2nd)
Shohei Ohtani 2296 96.7 9/19/23 (2nd)
Luis Severino 1515 96.6 2/27/20
Jésus Luzardo 2337 96.5 3/22/16
Zack Wheeler 3727 96.4 3/25/15
Frankie Montas 1554 96.4
Brandon Woodruff 2352 96.3
SOURCE: Baseball Savant and the Tommy John Surgery Database
Minimum 1,000 four-seam fastballs.

Some of those pitchers have had little trouble recovering and maintaining their elite velocities after their first such surgery, but as the sagas of deGrom and Ohtani illustrate, that hardly makes them immune from needing a second procedure. As the big contracts of so many of the pitchers above remind us, velocity gets pitchers paid, and so discouraging them from throwing at maximum effort with such frequency may be a tough sell, particularly when the next guy is willing to do so, damn the consequences.

This is all one big, thorny mess that won’t be solved overnight. The sad fact is that dozens or even hundreds more pitchers will be injured before we see if MLB can introduce meaningful steps to curb injury rates. In the meantime, teams will just turn to the next man up — and if he gets hurt, the next man up after him — to get by.

Brooklyn-based Jay Jaffe is a senior writer for FanGraphs, the author of The Cooperstown Casebook (Thomas Dunne Books, 2017) and the creator of the JAWS (Jaffe WAR Score) metric for Hall of Fame analysis. He founded the Futility Infielder website (2001), was a columnist for Baseball Prospectus (2005-2012) and a contributing writer for Sports Illustrated (2012-2018). He has been a recurring guest on MLB Network and a member of the BBWAA since 2011, and a Hall of Fame voter since 2021. Follow him on Twitter @jay_jaffe... and BlueSky

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1 month ago

It’s not just FG commenters who get all worked up over SSS data.

1 month ago
Reply to  sourbob

Did you read the piece? I don’t think that’s what this article is either? Jay basically just explains the hubbub and shows that you probably can’t blame the pitch clock – or, at least not more than you can blame velo and spin. The vibe I got here was “gee this sucks,” not “something must be done”.