Jeremiah Estrada, The Unsung Hero Of One Of The Best Bullpens In Baseball

[Greg Spicer]

Since 2024, the San Diego Padres have assembled one of the most dominant bullpens in the MLB. This performance has been headlined by a variety of big names who have deservingly gained a lot of spotlight. In 2024, they had two All-Star back-end arms in Robert Suarez and Tanner Scott, and Suarez is poised for a second consecutive appearance in the midsummer classic. In addition to those big names, Jason Adam has established himself as a dominant pitcher, garnering significant attention as a 2024 deadline addition. 

This stacked squad has also led to on-field success. Since 2024, the Padres' bullpen has ranked in the top three in FIP (3.58), WAR (8.3), and BB/9 (3.08). These numbers are supported by top ten ranks in ERA, saves, and K/9 as well. With so much success and so many big names, it’s easy to be overlooked when analyzing San Diego’s relievers. The main culprit of this has been Jeremiah Estrada. He has quietly become one of the best relief pitchers in the MLB and the catalyst for San Diego’s bullpen improvements beginning in 2024. 

Estrada, the sixth-round pick who makes just $777,000, turned his career around in 2024 when the Padres acquired him from waivers after being released from the Cubs in an abysmal decision. Since joining the team, his time in San Diego has been nothing short of brilliant. 

The 26-year-old right-hander has a three-pitch arsenal including a fastball, slider, and split finger changeup with 60-20-20 usage rates. This repertoire has led to a 2.25 FIP (7th in MLB), 2.3 WAR (7th), and 13.76 K/9 (4th) since the 2024 season. Not only are these numbers dominant, but they are also sustainable. His 87 2/3 innings pitched in that time frame represent a huge sample size, and the .290 BABIP is more likely to drop than increase, potentially improving his performance. The other counting stats support this data as well, as his 2.77 ERA, 0.72 HR/9, and 3.29 BB/9 are more than respectable. 

Although certainly impressive, Estrada's emergence was far from predictable. In Chicago, he was given limited opportunity and wasn’t able to do much with it. In just 16 1/3 IP before 2024, he put up a 7.37 FIP with 8.27 BB/9 and 2.76 HR/9. The only indicator of potential was a solid 11.57 K/9, and even that number seemed unsustainable given his pitch mix. In his appearances, Estrada was essentially a one-pitch pony, throwing a 96 mph fastball 84% of the time. What little he did have of an off-speed was a slider that was thrown 13% of the time. While it was fine against righties, it was useless against lefties. Seventy-three out of 83 of Estrada's pitches against lefties were fastballs in 2023. 

Padres pitching coach Ruben Niebla and the rest of the staff deserve a lot of credit for finding Estrada’s talents. Estrada worked with the Padres during the 2024 offseason to implement two major changes that enabled him to become the pitcher he is today. The first was a much-needed increase in velocity. A 96 mph fastball and 83 mph slider mix can pass for a starter or location/off-speed specialist, but in today's age, a reliever with a two-pitch mix needs to throw heat. The other change Estrada worked on was adding a third pitch, particularly one that could make him viable against lefties. For this, Estrada began mastering the split finger changeup. 

In 2024, Estrada’s fastball made the jump from 95.7 mph to 97.2 mph, and the results followed. The xBA (expected batting average) of the fastball dropped from .346 to .197, and its Whiff% increased from 20.2% to 32.6%. What's even more exciting is that Estrada has continued to improve his fastball so far in 2025. While it’s getting hit slightly harder this year (likely due to small sample size), his velocity is up to 97.9 mph, a career high. The same pattern was then followed for the slider. Estrada increased his velocity from 83.1 mph in 2023 to 89.8 mph in 2024, resulting in a .225 xBA with a 32.8% Whiff Rate. 

The second notable change for Estrada came in the form of a third pitch. His split finger isn’t just any third pitch either; it’s one of the most dangerous changeups in baseball. After only challenging lefties with fastballs in 2023, Estrada threw his new split finger 129 times to lefties in 2024, and the results were astonishing. In its first season, the pitch had just a .136 xBA and a 51% whiff rate. Now, in 2025, the split finger has become even more unhittable. It is yielding a minuscule .066 xBA with a further improved 53% Whiff Rate. This new addition to the pitch mix transformed Estrada from an unsuccessful righty specialist to an arm that lefties fear to step in the box against. 

From a viewer's perspective, what makes Estrada’s arsenal so satisfying is that it always keeps hitters off balance. His 98 mph fastball and 89 mph slider have the velocity to keep hitters on their heels, and the 83 mph split finger has every batter lunging. Having a plus fastball with two elite off-speed pitches makes him effective against lefties and righties in any situation. While he may not be the biggest name coming out of the pen, don’t forget about the unlikely emergence of Jeremiah Estrada.

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