Five Questions About Jacob deGrom’s Season-Ending Injury

Just as there aren’t always foreshocks before big earthquakes, there aren’t always velocity losses, muscle strains, or ominous MRIs before baseball players tear their ulnar collateral ligaments. Some elbows blow out before the “check ligament” light comes on. Last month, 26-year-old Houston Astros righty Luis Garcia, who had never been on the injured list in either the majors or the minors, started against the Giants following back-to-back scoreless outings. He felt pain in his elbow after his fifth pitch, threw three more, and then exited the game. Less than three weeks later, he had Tommy John surgery. In Garcia’s case, the only sign of impending doom was his position: pitcher.

Other hurlers, like Rangers righty Jacob deGrom, are walking warnings from the surgeon general that throwing baseballs hard may be hazardous to your health. For them, the road to UCL surgery is paved with possible precursors. On Tuesday, Dallas Morning News reporter Evan Grant broke the news that deGrom is broken. The reigning best pitcher in baseball—say it with me: when healthy—has a busted UCL and won’t be back in action until late 2024, if not 2025. The soon-to-be 35-year-old, who had Tommy John surgery after his first professional season in 2010, has made seven trips to the injured list as a big leaguer, including three previous stints for elbow- or forearm-related ailments. The five-year, $185 million contract he signed with Texas last winter wasn’t insured, The Athletic’s Ken Rosenthal reported, because the premiums would have been “prohibitively expensive.” Instead, the contract included a conditional option for 2028 that could be triggered if deGrom underwent Tommy John surgery (or sustained any long-lasting elbow or shoulder injury) from 2023 to 2026. We can and should be bummed about deGrom’s injury, but we can’t say we weren’t warned.

Now that the predictable-but-still-disappointing torn-UCL scenario has come to pass, it’s time to ask hard questions. So let’s consider what this long-dreaded diagnosis means for deGrom’s career and legacy, the first-place Rangers, MLB’s larger injured-pitchers problem, and the title of baseball’s best arm.

Is this the end of peak deGrom?

For the past two years, deGrom has been an agonizing, tantalizing blend of dominance and fragility. Hitters rarely appeared to pose a threat to him, but his own body regularly betrayed him. Not only did he miss most of the 2021 and 2022 seasons while on the IL, but he rarely went long between day-to-day ailments that got him scratched or pulled prematurely from starts even when he was active. (In 2020, when he avoided the IL, he dealt with back tightness, neck tightness, and a sore hamstring.) This season started with more of the same: side tightness in spring training, wrist soreness that ended his April 17 start after four no-hit innings, and, finally, the forearm discomfort that forced him to leave his April 28 start in the fourth, following a final fastball and slider that didn’t travel at their usual peerless pace.

Amid all the injuries, deGrom remained the majors’ best starter on a per-inning basis. In his breakout 2018 season, when he won the first of back-to-back Cy Young Awards, deGrom amassed 9.0 pitching WAR, per FanGraphs; from 2021 through 2023, in the same number of starts (32) and 30 1/3 fewer innings, he racked up 8.5. His 1.08 ERA and 1.24 FIP in 2021 were the lowest in the live ball era (minimum 90 innings pitched). He still leads all pitchers in FanGraphs WAR dating back to the beginning of 2018, despite ranking only 34th in innings pitched. Among the 89 pitchers with at least 500 innings pitched over the same span, the FIP gap between deGrom (2.11) and second-place pitcher Max Scherzer (2.82) is roughly as large as the gap between Scherzer and 20th-place Sonny Gray (3.54). Among pitchers who threw 100-plus innings from 2021 to 2023, only relievers Emmanuel Clase and Brusdar Graterol had higher average fastball speeds. Even this season, deGrom leads all pitchers with at least 30 innings pitched in FIP (1.57) and K-BB rate (35.7 percent), and trails only reliever Carlos Hernández in velo (99.1). He’s like a lights-out closer with the workload of an ace starter.

Or, at least, he was. As his body has faltered and he’s demanded more of it on each pitch, deGrom has gone less and less deep into games. As spectacular as the sightings continued to be, they were increasingly sporadic and curtailed.

“I had days where I’d feel really good, days where I didn’t feel great,” deGrom said on Tuesday. “So it was kind of riding a roller coaster.” The pitcher was referring to his attempt to return from his latest injury, but he might just as easily have been describing his struggles to stay available and pitch deep into games over the past three years.

The longer this on-again, off-again acehood lasted—the more minor ailments accumulated, the more “minor setbacks” he suffered, the more times his teams used phrases like “for precautionary reasons” or “out of an abundance of caution”—the more frustrating it felt for all involved. On a late-April podcast, I ranted that I couldn’t take deGrom’s ligament limbo anymore; at least surgery would stop the scalpel from dangling over his head. I was being facetious; deGrom, I acknowledged, was the one who was hurting from his injury and absence from the field, and the best-case outcome was that he’d be spared surgery. But my tongue was nowhere near my cheek when I went on to call the deGrom spectator experience stressful. If anything, I noted, his physical fragility had altered my mindset such that when he was scheduled to start, I was less excited about the prospect of his brilliant pitching than I was worried about what would go wrong.

DeGrom is older than a lot of fans think: Though the late bloomer made his MLB debut six years after Clayton Kershaw, he’s only three months younger than the Dodgers lefty. (Despite his own injury issues, Kershaw has thrown 40 more regular-season innings than deGrom since the start of 2018, the year deGrom leveled up and Kershaw began a graceful decline.) Then again, he’s not so old that he couldn’t conceivably come back with that new-UCL smell and dominate again; he’s already defied typical aging patterns by throwing harder every year. Justin Verlander, whom the Mets signed this past offseason to replace deGrom after the latter left via free agency, underwent Tommy John surgery in 2020, when he was almost three years older than deGrom is now. Verlander returned to win a third Cy Young Award. Maybe deGrom will too.

At minimum, deGrom pinpointed the problem and is pursuing a solution that’s paid off for him (and many other pitchers) in the past. After not knowing what ails you, it can be a relief to get a diagnosis and a treatment plan, no matter how poor the prognosis. “Now we know what it is,” a sobbing deGrom said on Tuesday, sounding somewhat heartened by the thought. “So if anything, at least it’s clear.”

What does this news mean for deGrom’s legacy?

Neither a prolonged absence nor a return in a less effective form could diminish the splendor of deGrom’s peak. If that peak doesn’t extend deep into his late 30s, though, he can kiss Cooperstown goodbye. Losing the rest of this season and most, if not all, of next season is much more than a minor setback to his Hall of Fame hopes. It’s probably a deal-breaker, barring an incredible comeback.

In March, deGrom called making Cooperstown “the ultimate goal.” Yet as he acknowledged then, that started “with going out there and making 30 starts a year,” and now there’s no chance of that happening until 2025. Because deGrom didn’t make his major league debut until his age-26 season and lost additional playing time to the pandemic-shortened 2020 schedule, it was always going to be tough for him to make up for lost time in the eyes of the voters. After 2020, he seemed to have a shot, but the time he’s missed since then has lowered his likely ceiling to the point that it’s hard to make the math work. After deGrom made his last appearance of 2023—but before anyone knew it was his last—Hall of Fame scholar Jay Jaffe wrote, “Where the 2021 version of deGrom looked as though he might wind up with totals in the general vicinity of Sandy Koufax … and be a Koufax-like exception for Cooperstown, his case becomes less convincing if he can’t stay on the field.”

According to Jaffe’s Hall of Fame rating system, JAWS, deGrom’s career and peak (best seven seasons) values to date sit well below the Cooperstown standard for starting pitchers. Jaffe developed an adjusted version of JAWS’s peak component that scales seasons down to a maximum of 250 innings pitched, so as not to skew the baseline too far toward the sport’s early innings eaters. By that adjusted metric, deGrom rates just below the positional average—and just above Koufax, whose three 300-plus-inning campaigns get shaved down. But it would take a clearly Cooperstown-worthy peak to compensate for deGrom’s shortcomings on a career level, and unless he has another two or three Cy Young–caliber seasons, he’s not going to get there. (Johan Santana, who taught deGrom his changeup, had a higher peak, and he fell off the BBWAA ballot after one year.) As it is, deGrom is more than 600 frames short of the career workload of the even later-blooming Dizzy Dean, who has the lowest innings total of any MLB starting pitcher in the Hall of Fame.

Plus, missing the rest of this season deprives deGrom of a potential opportunity to pad his postseason résumé, which consists of only five starts, four of them from 2015. Speaking of which:

Can the surprising Rangers endure deGrom’s loss?

Before the season started, I didn’t think the Rangers were ready to take the leap. Reader, I was wrong, at least so far. Only the Rays have a better record than the Rangers’ mark of 40-20, and Texas’s major-league-leading run differential (+155) tops Tampa Bay’s by 23 runs. The Rangers haven’t been better than the Rays, but their underlying performance has been barely a hair behind. And that’s with only 30 1/3 innings from deGrom, the centerpiece of their active offseason.

Of course, that’s 30 1/3 innings more than they’ll get from deGrom the rest of this season. But deGrom wasn’t the Rangers’ only offseason pitching import: Nathan Eovaldi, who signed with Texas for $151 million less than deGrom did, leads all AL pitchers in FanGraphs WAR. DeGrom’s WAR ranks second among Rangers starters, but Eovaldi, Martín Pérez, Jon Gray, Andrew Heaney, and Dane Dunning give manager Bruce Bochy enough depth to weather deGrom’s loss—unless and until some of those guys get hurt, which wouldn’t be shocking. (Depth addition Jake Odorizzi is already out for the year.)

The Rangers rank fifth in FanGraphs pitching WAR thus far, but the bigger surprise is their excellence on offense and defense: While Texas’s lineup looked likely to be a stars-and-scrubs bunch, it’s been strong almost from top to bottom, thanks to continued mashing by Marcus Semien, Corey Seager, and Nathaniel Lowe, along with solid steps forward from the likes of Jonah Heim, Adolís Garcia, Josh Jung, Ezequiel Duran, and Leody Taveras. Only the Rays’ position players have produced greater offensive and overall value than the Rangers’.

Texas also sports a 132 tOPS+ with runners in scoring position, meaning that the Rangers’ OPS in those situations has been 32 percent better than their overall production. That’s by far the best mark in baseball this year, and it would be one of the best ever if sustained over a full season.

Of course, the odds are that this type of success with runners in scoring position won’t last. Couple that clutchness with the number of players performing above their previously established levels—Dunning, who was pulled from the pen to reinforce the rotation, likely can’t maintain his deGrom-esque ERA—and the Rangers seem to be a bit over their skis (which aren’t of much use in Texas).

FanGraphs expects the regression monster to bite the Rangers hard enough to reduce them to a .502 rest-of-season winning percentage. (It doesn’t help that few teams have a more daunting projected strength of schedule.) But given their great start, treading water would get Texas to 91 wins and quite likely a playoff berth. Without deGrom, the Rangers aren’t as well equipped to withstand the correction to come, to fend off the Astros in the AL West, or to advance in the postseason. But they still have the fifth-highest playoff odds of any club, and general manager Chris Young will be scanning the thin, slow-developing trade market for any arms who can plug the leaks on the staff (particularly in the pen). There’s no substitute for a healthy deGrom, but a healthy deGrom doesn’t exist.

Could MLB learn from deGrom’s Icarus act?

I’ve wondered for years, and will go on wondering, whether deGrom could’ve benefited from just throwing slower. Not slow; still fast! Just a little less fast. If he could win a near-unanimous Cy Young Award in 2018 when his fastball was sitting 96, did he have to keep pushing it until it sat 99? Those extra ticks may have made him even better on a rate basis—from 2018 to 2019, his four-seamer averaged 96.7 mph and he recorded a combined FIP of 2.32, compared to 99.0 mph and 1.78 from 2020 to 2023. But they may have made him more brittle, too: He threw 421 innings in those first two peak seasons, and only 254 2/3 in the following four.

We’ll never know for sure whether throwing harder was what did deGrom in, but it can’t have helped; it’s a testament to his mechanics that he lasted this long, but physics is undefeated. As I wrote last year, “Multiple studies published in the past few years suggest that while pitch velocity is only weakly correlated with elbow and shoulder torque across pitchers, it’s highly correlated with torque for any individual pitcher.” In other words, the more consistently a pitcher throws toward the top of their personal speed limit, the more strain they subject their arms to, and the more damage they can potentially do to their UCL, one of the weak links in the kinetic chain. And deGrom didn’t just raise his upper velo limit; he also tended to drive closer to it, as shown by the shrinking gap between his average fastball speed and his 95th-percentile fastball speed as his career has gone on.

Even with a wider range of speeds in his repertoire than he had when throwing 96, deGrom hasn’t varied his velocities much. Instead of taking some speed off to preserve his arm and energy and save something for the moments when he really needed it, he pumped high-90s or triple-digits heaters almost nonstop, prioritizing pitch quality over quantity. Not many starters have had less separation between their average and 95th-percentile four-seamers this season than deGrom, and most of the ones who have throw in the low 90s. The hardest thrower with less fastball-speed separation than deGrom is Drew Rasmussen, a two-time Tommy John surgery victim who’s on the IL with a flexor strain, which is sometimes a prelude to TJ.

DeGrom is hardly alone in chasing the velo monster. He’s just been among the best at catching it. (Only the Reds’ Hunter Greene has thrown more triple-digit pitches as a starter since 2020 than deGrom’s 316; no one else has thrown more than 120.) As illustrated by the graph below, MLB as a whole has moved in a max-effort direction, which could be why deGrom is one of many, many hurlers who’ve had elbow or shoulder issues this year. It’s an occupational hazard exacerbated by recent trends—and, perhaps, by the fact that it’s seen as less imperative to avoid damage to the UCL when repairing or replacing it is possible.

“It’s tough,” Mets pitching coach Jeremy Hefner said last July, when asked about slowing down deGrom. “Do you put a governor on a Ferrari?” If you don’t want it to be totaled, maybe.

It must feel great to be able to throw really hard; as deGrom’s former Mets teammate Noah Syndergaard recently (and exquisitely sadly) said, “I would give my hypothetical first-born to be the old me again.” Realistically, you can’t expect a young pitcher to take the long view and restrict themselves to save their arm for a future game. (After briefly being tempted by triple digits, former deGrom and Syndergaard teammate Tylor Megill resolved to stop feeling the need for speed, and now he has 0.0 WAR.) Nor can you expect teams to stop pushing their players to dig deeper and throw harder—not when scouts, “stuff” stats, and on-field results alike favor flamethrowers. It’s up to MLB to keep lowering the maximum number of pitchers allowed on the active roster, thereby incentivizing individual pitchers to pace themselves (and potentially lowering injury rates, strikeout rates, and reliever usage). Otherwise pitchers will keep throwing fewer pitches and innings than ever without actually being better protected.

It’s not easy to make a cautionary tale out of someone who became the best at something (not to mention one of the best-paid). Most pitchers would probably sacrifice a ligament or two if it gave them deGrom’s gifts for a few years. On the plus side, we got to see an ungoverned deGrom soar closer to the sun than any other starter, which gave us a glimpse at where the sport’s natural limits lie. The problem was, the wax was melting all the while. When deGrom surpassed all other pitchers and kept on climbing, Icarus became his only comp.

If deGrom’s reign as MLB’s best pitcher is over, who inherits the belt?

There’s no definitive method for determining the best pitcher in baseball, but unless you consider durability, as some systems do, deGrom passes any sniff, taste, or stat test. Have you had the debate about who you would want on the mound if you had to win one game? DeGrom—say it with me once more: when healthy—has been the best answer for a while now.

How long a while? We can try to answer that via FiveThirtyEight’s pitcher rating system, which compares pitchers’ rolling-average game scores, adjusted for era, ballpark, and opponent strength—“the model’s best guess as to how the pitcher would perform in a typical start.” According to data provided by Jay Boice, who developed the system, deGrom first took over the top spot in FiveThirtyEight’s ratings at the start of 2019, but he and Gerrit Cole traded the title back and forth until deGrom wrested it away on June 5, 2021. He’s held it ever since—a span of 410 days on which an MLB game was played. That’s the fifth-longest streak on record, behind only peak Pedro, a couple of pitchers who’ve come up previously in this article, and the young, healthy Herb Score:

As far as FiveThirtyEight is concerned, deGrom is still the best pitcher in baseball, until proved otherwise. He’ll hold the title until it becomes clear that he’s not coming back (in which case the end of his reign will retroactively be set to the day of his last pitching appearance, shortening his uninterrupted tenure to 371 days) or until someone surpasses his rating—which, given how good he’s been when he has made his starts, seems unlikely to happen before he comes back and, presumably, pitches worse at some point. (Per Boice, the only two pitchers who’ve ever gone out on top are Koufax and J.R. Richard.) However, if we’re looking for a non-injured pitcher, or we presuppose that the older, surgically re-repaired deGrom won’t be the same, we need another name. I don’t think there’s that clear an answer.

Using the same method, here are the current top 20, excluding other injured arms (Brandon Woodruff, Max Fried, Rasmussen, and Jeffrey Springs):

Even setting aside Ohtani’s bat, you could talk me into choosing at least eight of these candidates to be my one-game champion (Gallen, Strider, Valdez, Gausman, Ohtani, Castillo, Cole, McClanahan). The point is, there’s not a ton of daylight between the best and next-best option, either statistically speaking or going with your gut. Consider how good the guys on that list are, and then consider how far deGrom’s rating towers above theirs: Even in absentia, with his recent game scores suppressed by abbreviated outings, he boasts a 64.9. Which is one more reason to hope we haven’t seen the last of deGrom’s greatness—or, if we have, to treasure the memories.

Thanks to Lucas Apostoleris, Jay Boice, and Neil Paine for research assistance.