Declan Cronin Remains Home Run-Free in 2024

One thing I love about writing for FanGraphs is getting the chance to cover players who otherwise would receive little (if any) attention from sources outside of their own team’s market. On this little part of the internet, pieces about the Joe Blows of the league aren’t just allowed, they’re encouraged. Yet, almost 10 years ago, the great Jeff Sullivan hemmed and hawed before writing about one such player:

For a while, I’ve personally been interested in Tyler Clippard. I’ve considered on several occasions writing about him, and about him specifically, but on every one of those occasions, I’ve talked myself out of it, because it just never seemed relevant enough. Generally, people haven’t woken up and thought, today I’d like to read in depth about Tyler Clippard.

I get what Jeff meant. I felt the same way before I wrote this article, hence this introduction. Still, it’s a funny train of thought coming from a writer who was so well known for making his readers care about topics they didn’t realize they would have cared about until they started reading. There was no need for Jeff to justify the subject matter of his article, least of all at FanGraphs. It’s also funny because Clippard was coming off an All-Star season in which he pitched to a 2.18 ERA and 1.5 WAR in 75 games. He had been one of the best relievers in baseball for the past five years. Clearly, the landscape of baseball blogging has changed over the past decade; a player with Clippard’s resume wouldn’t even qualify as a niche topic anymore. Indeed, Clippard might as well be a Shohei Ohtani-level mega-star compared to the reliever I’m writing about today.

Declan Cronin is having a strange season – equal parts thrilling, disappointing, and just plain unusual. Like Jeff and Clippard, I’d been interested in writing about Cronin for a while, but I kept putting it off out of fear he wasn’t a relevant enough subject. Then Cronin was removed from his outing on Thursday with knee discomfort (he’s day-to-day for now), and I realized I didn’t want to wait to write this piece any longer.

The White Sox selected Cronin with the 1,070th overall pick in 2019, a pick number that probably already sounds fake to the youngest generation of fans. He was never a ranked prospect, only once appearing as an “Other Prospect of Note” on the White Sox list in December 2022. After a bitter cup of coffee with Chicago in 2023 (three home runs and a 9.00 ERA in 11.0 IP), he was DFA’d twice this past winter before landing in Miami. And yet five months into the 2024 season, he’s one of the top 25 relievers by WAR. He’s gone from late-round draftee and unranked prospect to one of the most valuable rookie relievers in baseball. That’s the thrilling part.

Unfortunately, despite his low FIP and high WAR, Cronin owns a middling 4.65 ERA. He has the second largest gap between his ERA and FIP among all qualified relievers. What’s more, the Marlins, already one of the worst teams in the league, have been even worse in his appearances; the Fish are 15-33 (.313) when Cronin pitches and 34-52 (.395) in the rest of their games. Thus, his excellent work this season has gone largely unnoticed. That’s the disappointing part.

Finally, the most unusual thing about Cronin’s season, and ultimately the reason I’m writing this piece, is the fact that he has already pitched more than 60 innings and has yet to allow a home run. Even for a pitcher who plays half his games at the homer-suppressing loanDepot park, that’s impressive:

Aside from his left knee discomfort, yesterday was another typical Cronin outing: high ERA (10.80), low FIP (2.57), no home runs, and an unusual number of innings pitched (1.2). Funnily enough, Cronin has gone exactly one inning in only 14 of his 48 games; he has either entered or been removed mid-inning in the majority of his appearances this year. But I’m getting off-topic. For the 48th time this season, Cronin entered and exited a ballgame without giving up a home run. He has faced 272 batters and none have taken him out of the yard. Assuming Skip Schumaker gives him a couple of days off his feet to rest his knee, Cronin’s homer-less streak seems safe through the end of August. Moreover, Cronin escaped a series at Coors Field unscathed by the long ball, and now the Marlins have no games remaining at any of the 10 most homer-friendly stadiums, per Baseball Savant’s park factors. There’s still a month left to play, but Cronin is getting closer and closer to becoming the first pitcher in a decade to throw at least 60 innings in a season without giving up a home run:

To be fair, plenty can happen in a month of baseball. All it will take is one home run, and Cronin’s season will no longer be the answer to a trivia question. That said, what he has already achieved is impressive in its own right. Dating back to 2002 (the first year data is available on our splits tool), only three pitchers have gotten through August with at least 60 IP and zero home runs allowed: Jake McGee (2014), Wade Davis (2014), and Jim Johnson (2008). Assuming Cronin makes it another two days, he’ll join them on that short list. What’s more, Cronin ranks second only to Johnson in batters faced through August without giving up a home run. To make Cronin’s accomplishment all the more impressive, home runs are more prevalent in 2024 (1.15 HR/9) than they were in either 2014 (0.86) or 2008 (1.00).

If Cronin can finish the year without allowing a long ball, he will become just the seventh pitcher in the past 30 years to throw at least 60 innings in a season without giving up a home run. That list currently features Davis (2014), Kelvin Herrera (2014), Brandon League (2014), Peter Moylan (2009), Johnson (2008), and Jason Isringhausen (2002). (McGee didn’t quite make it in 2014; he gave up a homer in his third-to-last outing of the season.) Furthermore, Cronin should comfortably reach the 70-inning threshold, unless his knee injury proves to be more serious than it seems. In that case, he would join Davis, Herrera, and Moylan as the only pitchers in the past 30 years to top 70 innings without a home run. Finally, if he keeps up his current pace, he’ll finish with about 75.0 IP and 329 batters faced. The last pitcher to surpass both of those totals without giving up a home run was Greg Minton in 1981, when the league averaged a mere 0.64 HR/9.

On top of all that, Cronin could also become the first rookie hurler since Jack Billingham of the 1968 Dodgers to throw at least 60 innings in a season without giving up a deep fly. Indeed, the fact that Cronin is a rookie might be the most exciting part of all of this. If he surpasses Billingham’s 70.2 IP and 293 batters faced without a homer, he’ll set new highs for a rookie in the integration era.

Unfortunately, Cronin’s 4.65 ERA is surely putting a damper on what has otherwise been a rookie season worth celebrating. That ERA is the highest of any pitcher to go at least 60 IP without allowing a home run since Eugene Bremer of the 1943 Cleveland Buckeyes (4.94 ERA). Among primary relievers (Bremer started eight of his 10 games in 1943), it’s the highest homer-less ERA since Hal McKain of the 1930 White Sox (5.56 ERA). Meanwhile, Cronin’s 110 ERA- is the highest homer-less figure since Tom Burgmeier of the 1972 Royals (138 ERA-).

So how is Cronin enjoying so much success in one aspect of his game without more success all around? A quick look at his Baseball Savant page shows that he lives and dies by inducing groundballs. His 58.6% groundball rate ranks in the 96th percentile. He also has an 89th-percentile barrel rate, although that’s closely connected to his groundball numbers; his 43.6% hard-hit rate ranks in the 14th percentile. Thus, he’s more susceptible to a high BABIP or poor defense behind him. Lo and behold, his .381 BABIP is the second highest among qualified big league relievers, and the Marlins defense has given him -1 OAA in support.

But back to the home runs. About 85% of home runs have been barrels this season. Exactly 0% of home runs have been groundballs. It stands to reason that a pitcher who gets grounders and limits barrels will keep the ball in the yard.

Cronin relies primarily on a sinker/slider combo he developed at Tread Athletics during his days as a minor leaguer in the White Sox organization. In fact, I’m 95% certain this is Cronin pitching in the first result that popped up when I Googled “sinker/slider combo” to try to figure out if I should write that phrase with a hyphen or a slash:

Both pitches boast well-above-average vertical drop, and both help him induce groundballs. Out of 145 pitchers who have given up at least 50 balls in play on sinkers this season, Cronin’s average launch angle of -7 degrees is the eighth lowest. Out of 100 pitchers with at least 100 BIP against sliders, his average launch angle of +7 degrees is the 17th lowest. Finally, out of 232 pitchers with at least 150 tracked BIP this season (all pitch types), Cronin’s +1 degree average launch angle is the seventh lowest.

It also helps that Cronin doesn’t give up much pulled contact when his opponents do manage to hit one in the air. According to Statcast, opposing hitters have pulled just 15.1% of fly balls and line drives against Cronin, compared to the 32.5% league average. Thus, pulled balls in the air make up just 6.1% of all contact he has allowed; the league average is 16.3%. Cronin has only given up one pulled ball with an exit velocity over 95 mph and a launch angle of at least 20 degrees:

Even that hit wouldn’t have been a home run in any of the 30 big league ballparks, per Statcast. Cronin has only given up four batted balls that would have been home runs anywhere, and only one of them would have left the yard at more than a handful of stadiums. This double off the bat of Josh Lowe would have been gone at 15 parks, but thankfully for Cronin, the Trop isn’t one of them:

As I am compelled to mention, Cronin is certainly due for some regression. Eventually, he’ll give up a home run. In fact, and ironically enough, if he continues to do such a terrific job inducing groundballs and limiting barrels, he can hope to give up many more home runs over the years. Those are the things he needs to do to enjoy a long major league tenure, and home runs are inevitable in any pitcher’s career.

So, for his own sake, I’m rooting for Declan Cronin to give up another home run someday. But for my own sake, and for the sake of baseball trivia fans everywhere, I’m hoping he can hold off the inevitable for just a month longer.