2025 Fantasy Baseball Draft Sleepers List - Nick Mariano's Picks

Nick Mariano's 2025 fantasy baseball draft sleepers list for hitters and pitchers. His top fantasy baseball value picks, underrated players to outperform ADPs.

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The word "sleeper" may have lost its meaning across the industry so allow me to define it here. Fantasy baseball sleepers once meant "relative unknowns" -- but now we're just rolling with underrated players who stand to blow past their draft cost. As a result, you will find youngsters and veterans alike.

This piece utilizes consensus ADP from ESPN, CBS, Yahoo, RTS, and NFBC. These guys deserve more attention going into 2025 and can supply later picks that can vault our fantasy teams to the top.

Fantasy Baseball Draft Sleepers - Hitters

Catchers: Austin Wells (ADP: 212, C13)

Wells emerged as a great defensive catcher for the Yankees who rode a timely hot streak from July to August into the starting role and cleanup duties. But a horrid, unlucky September slump pushed him back off of most radars.

Jose Trevino is now in Cincinnati and no clear threat to playing time remains. Giancarlo Stanton (elbows) is already ailing so while it won’t be cleanup, Wells may hit fifth or sixth within a potent order and venue.

The 25-year-old has the second-best power park for left-swinging bats, per Baseball Savant. From late June on, Wells held a .243/.336/.446 triple slash with 11 home runs and 10 doubles across 67 games (260 plate appearances). This includes an icy September where he hit .111 with a .135 BABIP after a .265 July mark and a .375 rate in August.

Despite that, his barrel and hard-hit rates remained unchanged from August to September. But his job security was bolstered by a 96th percentile framing rate and 75th percentile blocking rate behind the dish. With more experience and a reinforced roster around him, Wells offers a cheap 25 HR upside with healthy run+RBI tallies.

Others I Like: Sean Murphy (237), Connor Wong (242), Ivan Herrera (297)

First Base: Michael Toglia (ADP: 220, 1B21)

Toglia’s low-contact, high-power profile had pigeonholed him as a role-playing pinch-hitter for the Rockies, but he struck a better balance through more consistent play when recalled in June. His overall .218/.311/.456 slash line over 116 games (458 PAs) came with 25 HRs and 10 steals, as well as a home/road split that will surprise most.

Colorado players are supposed to overperform at home, yet only eight of the 25 HRs came there. It’s not a volume trick either, with 228 home PAs and 230 road PAs. He also didn’t have increased strikeouts on the road, though his .333 Coors BABIP tumbled to .207 on the road. It’s not all a surprise.

Throw out a brief April stint before a Triple-A experiment saw him hit safely in 23-of-30 games The switch-hitter then had a .233/.331/.369 slash over the final 101 games (409 PAs) with 21 HRs and all 10 SBs. The 13 percent walk rate, power, and sneaky speed made the 31 percent strikeout rate palatable, both for the Rockies and fantasy managers.

By September he was regularly hitting fourth or fifth in premium R+RBI slots. If he can hit around .230 with another 30 HR/15 SB pace from a last-round pick then we’re thrilled. Don’t forget his teammate Brenton Doyle also had exciting HR/SB tools but a horrid 35 percent strikeout rate in ‘23 before breaking out. Never turn your nose up at a cheap Coors ceiling.

Michael Toglia had a 16.4% Barrel% after the All-Star Break.

Only 5 players had a higher Barrel% over that span:

Aaron Judge
Shohei Ohtani
Kyle Schwarber
Juan Soto
Jorge Soler pic.twitter.com/qRB6P0ztxw

— Kirk Snyder (@dynastyinfo411) January 27, 2025

Others I Like: Ryan Mountcastle (252), Rhys Hoskins (255), Nolan Schanuel (323), Kyle Manzardo (373)

Second Base: Luis Rengifo (ADP: 209)

Rengifo is fully recovered from last year’s wrist surgery and ready to build on the 78-game breakout that saw him hit .300 with six homers and 24 steals. Anything remotely resembling a 50-game SB pace deserves more respect than this. Especially when it comes with a strong batting average.

Now, Rengifo only had a .262 xBA but has consistently outperformed the metric, hitting .264 in both ‘22 and ‘23 with xBAs of .254 and .246, respectively. The biggest change came in his fly-ball rate going from 28 to 17 percent, including his pop-up rate falling from 6 to 4.2 percent (per Statcast). More grounders and line drives led to more hits and SB opportunities amidst the power drop.

The 28-year-old doesn’t boast extreme speed but found his comfort on the basepaths, going 24-of-31 in under half of a season after never attempting more than 10 in a year. If he hits .270-.275 with even a 10 HR/30 pace then we’re profiting, let alone if the speed pace picks up where he left off.

Others I Like: Brendan Donovan (230), Jonathan India (231), Thairo Estrada (323), Caleb Durbin (377)

Third Base: Matt Shaw (ADP: 257)

Shaw has emerged as a favorite to win the hot corner job at Wrigley after a stellar age-22 season between Double- and Triple-A. He hit .279 with an .841 OPS, 14 home runs, and 25 swipes in 86 Double-A contests before a .298 average and .929 OPS (7 HRs, 6 SBs) in 35 Triple-A games must’ve left management confident going into this year.

To those Shaw is a new name for, he was the 13th overall pick of the 2023 Amateur Draft and had a .357/.400/.618 triple slash with eight long balls and 15 steals in just 38 games as a first-year pro. He has yet to experience an obvious challenge, sporting a strikeout rate below 20 percent at each level.

Most projections have him hitting around .250 with 15/15 potential, but even if his power peak is years away, the 23-year-old’s plus speed could blow past that if comfort timing MLB pitchers comes early.

Others I Like: Josh Jung (223), Joey Ortiz (297)

Shortstop: Tyler Fitzgerald (ADP: 257)

He’s shortstop eligible to begin the year but will move to second as Willy Adames mans the six. The Giants have very little by way of competition for reps up the middle and one hot streak from Fitzgerald pays for the minimal investment. In 96 games last year, Fitzgerald performed well against both lefties and righties as well as at home and away.

His 15 HRs and 17 SBs in just 341 PAs is plenty promising, with Fitzgerald claiming that laying off sliders and increasing walks as an area of focus in ‘25. But the biggest fantasy piece is his relaying that he’s “going to steal as much as [he] can,” as detailed in a recent Susan Sussler piece.

Everyone talks a big game but Fitzgerald has the jets to back it up. His 30.0 feet/second sprint speed is easily in the top 10 and tied with Elly De La Cruz. How’s that for a comp? It’s not everything, but having just gone 17-of-21 last year and owning a 90 percent success rate in the minors going back to 2022 means the ceiling is higher than most know.

Others I Like: Trevor Story (288), Luisangel Acuna (357), Jacob Wilson (360)

Outfield: Garrett Mitchell (ADP: 309)

I will briefly point out that Parker Meadows still has early ADPs around 260 on Yahoo and ESPN, making him a fun click.

Mitchell has shown flashes as a pro but injuries have robbed us of seeing him shine. An oblique injury stole two months from him in ‘22 and a torn labrum in his left shoulder limited him to 19 games in ‘23 before a fractured finger suffered in Spring Training pushed his ‘24 debut into July. It was a slow re-entry but he got his timing back in two weeks, logging his first homer and steal of the year on July 14.

That sparked a 60-game stretch with eight homers and 11 steals with a .266 average to finish the year, which is a rough 20HR/25SB pace. And he was largely being platooned away from southpaw pitching, a situation that could change with Christian Yelich able to DH as Sal Frelick and Blake Perkins rotate more in left field.

Perhaps the strikeouts become a breaking point, but much like Toglia, Mitchell has a double-digit walk rate to ease the pain. And Mitchell plays a mean outfield with an 83rd-percentile arm to go with plus range.

Mitchell may not beat Tyler Fitzgerald in a footrace, but his 29.5 ft/sec sprint speed still ranked 30th of 566 tracked players last year.

Outfield: Jung Hoo Lee (ADP: 255)

We only got 37 games of Lee before a wall collision prematurely crashed the rookie’s MLB party. While his .262/.310/.331 slash line with just six extra-base hits (two homers) and two steals doesn’t jump off of the page, there were signs of more to come.

Lee only had six barrels but half of them came in his final seven (complete) games. Out of 405 hitters with at least 100 batted-ball events, Lee’s 41.8 percent hard-hit rate was 133rd. That’s squarely above average and this was him adjusting to the bigs!

His 91.5 percent contact rate trailed only Luis Arraez and Steven Kwan and those profiles have certainly worked out for us. Now there are reports that Lee may hit in the valuable third spot.

A penchant for contact with runners on would yield healthy RBI totals to go with the strong average. We must point out that he got caught stealing three times compared to just two successful swipes, but better timing comes with experience, or else the perpetual red light will halt him.

Others I Like: TJ Friedl (273), Jordan Walker (308), Jo Adell (328), Jacob Young (335)

Fantasy Baseball Draft Sleepers - Pitchers

In 2023 we snagged Hunter Brown and Justin Steele out of here, and last year Cristopher Sanchez popped. Who’s next?

Starting Pitcher: Kumar Rocker (ADP: 302)

Rocker only made three short starts in the majors down the stretch but what we saw was plenty enticing. He got a gift matchup for an MLB debut in Seattle against the whiff-happy Mariners, who struck out seven times over four frames of one-run ball. He would have more modest results against Toronto and Oakland, but the overall 14:6 K:BB in 11 ⅔ IP is worth a discussion.

Some may look at this and see a fireballer throwing without command, but that would be a small-sample folly. He may not have many professional innings under his belt, but 2022’s third overall draft pick does not issue free passes lightly.

His 42:7 K:BB in 28 IP at High-A after being drafted was crispy and then he posted a ridiculous 55:5 over 36 ⅔ IP, with five starts at Double-A and a pair at Triple-A before the promotion. On top of elite whiffs and control, Rocker also attacks under bats and should supply a groundball rate near 50 percent.

For now, Rocker is on the outside of the Texas rotation. But how many of you are drafting as though Jacob deGrom, Nathan Eovaldi, Jon Gray, Tyler Mahle, and Cody Bradford will all be healthy even by May 1?

Gray barely hit 100 frames last year and had bullpen reports floated, while deGrom and Mahle are coming back from major surgery, and Bradford has never thrown a complete year as a starter (roughly 90 IP across all levels last year). Let’s stash this upside away!

Starting Pitcher: Grant Holmes (ADP: 353)

The buzz around Holmes is minimal considering the numbers he compiled in 2024 between the bullpen and rotation. Before we introduce any splits or cherry-picking, consider his 3.56 ERA was bested by the 3.20 FIP, 3.52 xFIP, and 3.37 SIERA.

His 1.19 WHIP was stellar and rooted in a robust 5.3 percent walk rate rather than a fluky BABIP. His 43.8 percent groundball rate is good and the 16.4 percent swinging-strike rate is juicy.

According to the FanGraphs leaderboard, Holmes’ swinging-strike rate actually went up to 16.7 percent as a starter. It’s a small sample, but that would’ve led the majors. Only four pitchers (min. 30 IP starting) managed a SwStr% above 15 percent: Robbie Ray (16.2), Garrett Crochet (16.2), Blake Snell (16.3), and Holmes at 16.7 percent.

Of that group, Snell and Ray pair the whiffs with a double-digit walk rate. Like Holmes, Crochet also had a 5.5 percent walk rate and the 45 percent groundball rate also tracks. Not bad company, eh? Worth a flier?

And now my one cherry-pick: Of Holmes’ seven starts, one of them came at Coors Field. He gave up five runs with three walks over five innings. It was his only appearance with more than two walks or three runs allowed. And he still had those great numbers overall!

AA stated in Oct Grant Holmes would be stretched out to start. They believe in him.
109 IP in 24 w/3.21 ERA, 121 K, 29 BB
SL & CB: 25% & 24% SwStr%, both 90th percentile or higher. Mid-90s FB will play. Advanced strike thrower. Could make 20 starts in 25pic.twitter.com/K2EaUKsvjF

— Chris Clegg (@ChrisCleggMiLB) January 23, 2025

Others I Like: Reid Detmers (382), Sean Burke (399), Noah Schultz (506), Hayden Wesneski (522)

Relief Pitcher: A.J. Puk (ADP: 284)

The 2024 starting rotation experiment was a disaster thanks to minimal command (12:17 K:BB in 13 ⅔ IP) and led to shoulder fatigue after a seven-run meltdown. He missed a month and then returned as a reliever, though he still didn’t look himself with just one strikeout in his first six appearances. Things didn’t seem to click until mid-June and then we were off to the races.

That his overall 3.15 ERA (2.87 FIP) and 88:28 K:BB still looked strong is miraculous given the start, but you need to see the splits to appreciate it. Puk’s first 18 games yielded a 6.91 ERA (5.43 FIP) and a horrid 20:20 K:BB in 27 ⅓ IP. He still avoided barrels (4.3 percent) but he wasn’t right.

Well, his final 44 games brought an insane 0.82 ERA (1.28 FIP) with a 68:8 K:BB over 44 IP. Only Emmanuel Clase had a better ERA among 179 qualified RPs in that window. No one bested the 42.5 percent strikeout rate.

Edwin Diaz was the only one to top 40 percent and he had a 10.7 percent walk rate to Puk’s 5 percent mark. The 37.5 percent K-BB rate was 4.5 percentage points ahead of the next man (Dylan Lee), which is an astounding margin at this level of competition.

Justin Martinez is no slouch and may indeed grab the majority of Arizona’s save opportunities. But even if Puk only snags 8-10 saves, you cannot turn your nose up at that ratio and strikeout-per-inning upside.

Relief Pitcher: Chris Martin (ADP: 350)

We’ll keep this lighter as Texas may still bring someone in, such as David Robertson, to oust Martin from the inside track on the ninth. For now, the 38-year-old with a career 3.38 ERA/1.13 WHIP who regularly supplies over a strikeout per frame and just posted a career-low 1.7 percent walk rate is the Rangers closer.

Perhaps Robert Garcia grows into the southpaw platoon-mate of sorts but no one has Martin’s track record in this bullpen. He’s always filled in admirably when called upon, securing at least one save in each of the last six seasons. The record of healthy ratios and whiffs should be an easy late-round snag for us to jam.

Others I Like: Robert Garcia (484), Mason Montgomery (633), Craig Yoho (769), Ryan Zeferjahn (832) -- Update: Removed Prelander Berroa section due to TJS...sigh. Mike Clevinger is a flier.

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