Relief Pitcher Fantasy Baseball Breakouts - Undervalued Closers and Saves

March 23, 2025

John Laghezza's favorite relief pitcher fantasy baseball breakouts and sleepers - undervalued closers and saves to target at the end of 2025 drafts at a discount.

With Saint Patrick's Day firmly in the rearview mirror, we're officially rounding third and heading for home! After months of preparation spent digesting mountains of data, there are always some things bound to slip through the cracks. For me, that gap usually manifests as relievers — usage can be wonky, performance inconsistent, and roles always seemingly under threat.

After losing Edwin Diaz in a World Baseball Classic celebration, I stopped paying reliever premiums. So, as a born-again habitual RP punter, I can't help but stress opportunity cost and prioritize everyday hitters or top-tier starters over chasing saves.

That said, it's still a meaningful category and cannot be ignored outright. So what do we do? How do we go about manning our fantasy bullpen? I generally find myself digging through the middle rounds for one reliever that can finish in the top five at the position, then dumpster-diving for potential breakouts in the endgame.

Today, we'll make a few calls to the pen with one goal in mind: finding the best combinations of skills and roles to identify the relievers I'm actually willing to shell out precious draft capital for. I proudly present my breakout relievers for 2025. Average ADP Data per Yahoo, 3/23/25.

Jeff Hoffman, RP, Toronto Blue Jays

ADP: 120

Finally, fake news serves as a positive in my daily life. Despite the usually stingy Blue Jays giving Jeff Hoffman a $33M dollar bag this offseason, drafters continue to let him slide down draft boards. Why? The market's still hung up on the Brewers, Orioles, and Red Sox, citing failed physicals regardless of the fact they all reportedly pursued him to start.

No one's quite sure what they saw on those doctor's reports, and I won't pretend to play doctor here, either. However, one thing's for sure — Hoffman's taken the ball each of the last 122 times he's been called upon in the previous two years without a single missed game.

So, I ask you, at what point do we stop being worried about injuries? Upon leaving Cincinnati for the City of Brotherly Love, Hoffman finally realized his full potential by improving his arsenal, namely adding more than two miles per hour to both his four-seam fastball and sinker.

The results? Devastation for opposing hitters, absolutely bearing out in the box score — just look at the precipitous jump across the board before and after signing on with the Phillies.

• ERA: 5.68 Before, 2.28 After
• WHIP: 1.58 Before, 0.94 After
• SIERA: 4.89 Before, 2.65 After
• BAA: .271 Before, .178 After
• K%: 20.3 percent Before, 33.4 percent After
• BB%: 11.1 percent Before, 7.4 percent After
• HR/9: 1.63 Before, 0.68 After

Hoffman now boasts three separate pitches with a +32 percent whiff rate, including his featured slider with all the diagnostic bells and whistles that can only be described as unhittable — 40.8 percent use, 86.8 mph, 2830 rpm, 38.8 inches of vertical drop, .178 xBA, .316 xSLG, 45.2 percent whiff. Wow! Going this deep in drafts, he's easily my top mid-round reliever.

Toronto's new closer Jeff Hoffman got big money & a clear path to the closer role on a team known for using a single guy to slam the door

And oh yea, he's unhittable pic.twitter.com/tnYUfAuAYA

— John Laghezza MLB / NFL Moving Averages (@JohnLaghezza) March 21, 2025

Chris Martin, RP, Texas Rangers

ADP: 190

Pitchers like Texas' recent free agent acquisition Chris Martin fly in the face of the conventional 21st-century closer archetype. You won't get 100-mile-per-hour fastballs, oohs and aahs, or internet helium. What you get, however, is everything that matters between the lines.

Granted, there have been a few arm-related injury scares in the recent past (sore shoulder, elbow inflammation). That said, he's bounced back each time to great results, and the Rangers paid him $5.5M to slam the door on games in 2025.

At 38 years old, we may not be buying in for a long time, just a good one. With very little competition currently residing in the Rangers' pen (no one had more than two saves in 2024), it's presumed Martin's the guy — and that's something. Remember when you've been frustrated as a fantasy gamer watching your high-skill relievers burn up in high-leverage seventh or eighth-inning spots. The only thing that matters in category play is role, and for right now, we should have a firm grasp on it.

Again, the arsenal's not going to stand toe-to-toe with the more devastating closers in the game, but who cares? Over the last three seasons, Martin's done everything we could ask for in terms of closer stability besides a very low 2.37 ERA — low WHIP (1.04), miniscule walk rate (2.6 percent), chases outside the zone (38.5 percent O-Swing), tons of grounders (48.9 percent GB), contact suppression (35.5 percent Hard Hit, 4.8 percent Barrel) and no longballs (0.77 HR/9).

It may not come in the packaging we're used to, but that skillset will play — especially considering the cost.

Chris Martin, 95mph Two Seamer and 93mph Cutter, Overlay pic.twitter.com/1rPJHm88gc

— Rob Friedman (@PitchingNinja) June 12, 2023

Aroldis Chapman, RP, Boston Red Sox

ADP: 216

Speaking of the hard-throwing, thrill-a-minute reliever archetype, does any player embody that more than the newest Red Sox RP, Aroldis Chapman? The 6-foot-4 lefty's 37 years old, but you wouldn't know it from his 98 mph heater.

Currently MLB's third-leading active save leader (335), Chapman's still got it on the hill. Through a distinguished 15-year career, he's got just a single season logging a strikeout rate under 33 percent. That is unbelievable stuff from a future Hall of Famer closer.

Often thought of as just a consistent four-seam fireballer, Chapman's evolution through the years deserves some attention. What started out as almost a purely fastball-only approach (+80 percent use through seven seasons) has developed into a more nuanced arsenal.

Throttling the four-seam utilization rate over the years down to the mid-30s, he's even ditched the tertiary changeup for a sinker and split-finger since the 2000 season. The results? Unsurprisingly excellent — all three secondaries in the current iteration of his arsenal limit hard contact (maximum .301 xSLG) while inducing tons of swings and misses (minimum 31 percent Whiff).

While the walk rate's always jumped off the page a bit (career 12.6 percent BB), the command's not nearly as bad as it looks through a more granular lens. Believe it or not, Chapman's career 36.2 percent ball rate aligns with the long-standing league average. Mind-blowing stuff, right? The fact remains: This leopard's not about to change his spots. Chapman is willing to offer the occasional free pass because he can always get the next guy between his dominance to win in the zone (career 72.0 percent Zone-Contact) and refusal to surrender home runs (career 0.60 HR/9).

So now that we feel secure in his abilities, what about his role? Early in draft season, the market assumed the job belonged to Liam Hendriks if ADP was the leading indicator. I hate saying anything about Hendriks, by the way. He's a great guy with an even greater story — a true inspiration in his cancer recovery. However, he hasn't thrown a professional pitch since early June of 2023 and has shown every bit of that rust so far this spring.

Through 6 1/3 IP, Hendriks is sporting a 9.96 ERA, 2.21 WHIP combo, and a disastrous 2.84 HR/9. While he could turn it around with more repetitions, I'm struggling to think he'll get the initial opportunities for a vastly improved Boston squad looking to make a deep run in a wounded A.L. East division. It's not set in stone.

Red Sox beat reporter Chris Cotillo's on record saying, "The Red Sox have not finalized roster decisions yet, but as things stand now, Aroldis Chapman (closer) is in a good spot to win his roster battle."

Aroldis Chapman strikes out the side in the 8th inning and shows off his new 77mph breaking ball against Javy Baez. pic.twitter.com/PsRheNWRR0

— Boston Strong (@BostonStrong_34) March 19, 2025

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