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Top 10 MLB Free Agent Relief Pitchers for 2025

Top 10 MLB Free Agent Relief Pitchers for 2025

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Clay Holmes (Photo by Luke Hales/Getty Images)

October baseball is in the air, which means the offseason isn’t long in coming. We identify the top MLB free agent teams that could be targeted this winter by taking a data-driven approach to this year’s group of players.

Below is our breakdown of the 15 best free agent relief pitchers in the 2025 class, with an emphasis on material quality and high-leverage experience. We dive deep into the top 10.

Our list leverages the work of MLB Trade Rumors for the free agent roster, as well as FanGraphs, Baseball Prospectus and Baseball Reference for player win values ​​above baseline, Baseball Prospectus for DRA, StuffPro and PitchPro, and FanGraphs for all other data, including Stuff+ and Location+. We encourage our readers and subscribers to consider subscribing to FanGraphs and Baseball Prospectus as well.

Luke Weaver has replaced Holmes as the Yankees’ closer, which strongly suggests the Yankees will pick up his $2.5 million option, so we won’t include him on this list. Despite having issues with failed saves, Holmes has an absolutely electrifying arsenal:

Holmes has the classic Supinator arsenal: a fantastic sinker and sweeper as well as a gyro slider. This video from Tyler Zombro of Tread Athletics does a great job breaking down pronation bias versus supination bias:

All three of Holmes’ pitches are plus pitches or better. Let’s take a look at how StuffPro looks at the arsenal, with negative numbers representing run prevention per 100 pitches:

Year Sinkers Slider sweeper
2022 -1.1 -1.4 -2.2
2023 -1.1 -1.8 -3.1
2024 -0.9 -1.3 -3.2
Clay Holmes’ StuffPro breakdown

That’s three pitches that all prevent runs at least one run per 100 pitches better than average, and a sweeper that is one of the best pitches in baseball. The sinker receives a lot of seam-shifted wake depth and sinks about 8 to 9 inches more than the axis of rotation would indicate, resulting in a negative launch angle of six degrees in 2023 and a negative launch angle of four degrees this year. His sinker has a mirrored axis of rotation to both the sweeper and gyro slider, which likely contributes to pitch deception. Stuff+ doesn’t break out the slider and sweeper, but has given them combined grades of 142, 141, 159 and 234 this season.

Given his ability to utilize seam effects, I think he could have a killer substitution if he wants to add another weapon to his arsenal. However, his arsenal is so good that he doesn’t really need it, especially if he stays in the bullpen. Even though he tops this list as a relief pitcher, I think he’s a fantastic candidate to replace Garrett Crochet next year.

Holmes has a starter’s frame of 6-foot-5, 245 pounds and has been a starter throughout his minor league career, including as recently as 2018. His weight-heavy approach would allow him to move through lineups efficiently. If he adds a changeup, he could have more than four throws, more than enough to get through lineups multiple times. Since Weaver has moved up to closer with the Yankees, it wouldn’t surprise me if they found a way to keep Holmes and turn him into a starter.

Scott is very easy to explain as he has a great FF/SL combination:

His fastball averages 97 mph, which is about 2.5 inches more ride than expected given his release characteristics. He receives a lot of criticism on the field, although his zone rate of 53.6% is still below what you would like. His slider maintains a ton of depth and is a perfect complement to the fastball. His command has improved just enough in 2023, and it looks like he’ll dominate hitters with electric means for years to come.

Hoffman is an elite, high-leverage bullpen arm, although he doesn’t have the “proven closer” tag that some teams covet.

His stuff isn’t quite as electric as Scott’s, but his fastball has great velocity and shape. He tends to throw the ball up the middle frequently, even when off-field batters don’t hit home runs:

His gyro slider features death ball movement, achieves negative vert and a massive 22% swing hit rate (per pitch). His shard also produces a lot of scent, even though he doesn’t throw it very often. Hoffman has the skills and experience to finish games wherever he signs.

Over the last two seasons, Chapman has thrown 120 innings and struck out over 200 batters. With a K% rate of almost 40%, he was already showing off his still elite stuff in the second half of his 30s. His command comes and goes, and he hasn’t posted an ERA below 3.00 in five years, but he’s an elite strikeout artist and it looks like he’ll stay that way as long as he pitches.

Jansen is no longer the pitcher he once was, but he is still a reliable “proven closer” who has returned to his roots and increased his cutter usage to nearly 85% this season. According to FanGraphs, he has been at least 0.83 runs per 100 pitches better than average in every season of his career except 2019. The lower use of his sinker and slider helped them emerge as surprise pitches. He only hurls the pitch at a speed of 92 miles per hour, but it has been moving at that speed for nearly a decade, so there’s no reason to think that won’t be the case for much longer.

Treinen is finally healthy, although he’s not quite back to his former self yet, having lost a few ticks on his sinker. However, he is the Dodgers’ closer in the playoffs, which should tell you everything about how much they trust him. Despite the reduced velocity, Treinen still posted an ERA under two and has posted a 2.29 ERA over 150 innings over the course of his injury-plagued Dodgers career. It can take pitchers a long time to recover from shoulder injuries, and it looks like Treinen is finally getting back to his old self.

Estevez has a great fastball that hits 96-97 mph and travels more than two inches above expectations based on his release characteristics. My SMOKE score is about 0.75 runs/100 pitches above average and Stuff+ is 109, but StuffPro is more skeptical and sees only 0.2 runs above average.

He does a lot of changes, but it has terrible theoretical form with no drop and fade and performs very poorly from a technical point of view. However, the pitch gets a touch and isn’t hammered, so it’s possible the unusual shape works for him and he sells it well. The slider is a great pitch but includes all metrics. Estevez is a very good pitcher who has proven he can finish games.

Sewald had a poor season, but the data strongly suggests that this was due to reduced sampling noise rather than a massive drop in performance. While the Stuff models saw a decline in fastball quality, largely due to the loss of a tick to Velo, it was still rated as an excellent pitch: 119 Stuff+ (down from 134 last year) and -1, 1 StuffPro (versus -1.7 last year). Year). According to my linear SMOKE metric, it runs better than average at just 0.2, but it might be difficult to fully capture Sewald’s outlier features. He combines it with a great slider and mixes in a surprising variety every now and then.

Teams that value material models will likely have Sewald as their main target this offseason, especially after a down year in which he may come at a discount.

Stuff+ has always been a big fan of Loaisiga:

StuffPro is also a big fan (negative numbers are good, positive numbers are bad):

SEASON FASTBALL SINKER SWEEPER CHANGE
2020 -0.5 -0.9 -1.6
2021 -0.8 -1.8 -1.7 -0.8
2022 -0.3 -1.1 -1.4 -1.2
2023 -1.3 -2.3 -1.8 -0.8

It is extremely rare for a pitcher to have such a good sinker and four-seam fastball. He combines that with a plus-plus sweeper and a good changeup. That’s three plus-plus pitches and a fourth average pitch out of the bullpen. From a pure perspective, Loaisiga is clearly at the top of this list, and it’s not particularly close. Despite elite raw materials and above-average leadership, he has never quite produced the results that the metrics strongly suggest.

After undergoing UCL surgery in April, Loaisiga could finally be healthy again by mid-season. As one of the younger pitchers on this list with absolutely electric raw material, he appears to be a key target for teams looking toward the postseason and/or building the back of their bullpen for the next few years. If it all comes together, there won’t be many bullpen arms better than Loaisiga.

Garcia has an electric arsenal:

Stuff models love his fastball, which is easy to see given his plus-plus-velo and plus-plus ride characteristics given his release characteristics. For some reason he gives up a lot of home runs and isn’t quite as dominant as his raw stuff would suggest. I don’t really have a good explanation as to why he doesn’t perform like a ’70s closer given his raw qualities. So it wouldn’t surprise me if he had a great season as a closer somewhere, and it wouldn’t surprise me if he was just pretty good.

The best of the rest

AJ Minter has been a very reliable bullpen arm for most of his career, but is recovering from a hip injury that puts his health in question. Aaron Bummer has an elite sweeper, a terrible four-seam, and a decent sinker, making him a pull-heavy pitcher who performs much better against lefties than righties. He’s not a true specialist, but he needs an increase in sinker quality to be more than just a useful bullpen arm.

Kirby Yates and David Robertson are both in their late 30s but continue to chug along and produce. They’re probably boring pickups that smart teams build to bolster their bullpens. Kendall Graveman rounds out this list as an electric arm who may need some time to recover after shoulder surgery.