Samuel Basallo and Emmett Sheehan Lead the Top Fantasy Baseball Sleepers for 2026
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As we head into the 2026 MLB season, fantasy baseball managers are always on the hunt for undervalued players who could deliver breakout seasons.
In this list, we highlight the top sleeper players flying under the radar but with the potential to make a big fantasy impact.
All rankings and projections are based on the in-depth research from Shawn Childs on Substack, who provides one of the most trusted and detailed sources for fantasy baseball analysis today.
Whether you’re targeting late-round gems or waiver-wire steals, these sleepers are players to watch closely as draft season approaches.
Baltimore Orioles C Samuel Basallo: Rank 14, ADP 176
Samuel Basallo is a top fantasy baseball sleeper heading into 2026 because his minor-league track record suggests far more upside than his initial MLB numbers indicate.
In 2025, he debuted in the majors at age 21, hitting just .165 with 4 HR, 15 RBI, and a .559 OPS in 31 games, but his Triple-A production told a different story: he slashed .278/.341/.449 with 19 home runs and 10 stolen bases across 127 games, showing a rare mix of power, contact, and speed for a backstop.
Catchers with his profile are exceptionally scarce, and even modest improvements in average and home runs could vault him into top-10 catcher value while still being drafted late.
With a team committed to giving him playing time and potential eligibility at DH or 1B, Basallo offers significant breakout upside, making him a classic fantasy sleeper for 2026.
Houston Astros 3B Isaac Paredes: Rank 15, ADP 222
Isaac Paredes could be one of 2026’s most underrated fantasy sleepers, pairing genuine power with strong plate discipline that many drafters are overlooking.
In 2025, despite a hamstring injury, he slashed .254/.352/.458 with 20 HR, 53 R, and 53 RBI in 102 games for the Astros, showing he can contribute across multiple counting stats.
Projection systems suggest a full season could see 28–30+ home runs with league-average batting and solid OBP, giving him a higher ceiling than his current ADP indicates.
Drafted after many corner infielders, Paredes offers late-round value and the potential to outperform expectations, making him a classic sleeper for 2026.
Los Angeles Dodgers SP Emmet Sheehan: Rank 33, ADP 66
Emmet Sheehan is a 2026 fantasy sleeper who caught attention after returning from Tommy John surgery and could take a major step forward with a bigger role.
In 2025 with the Dodgers, he posted a 6‑3 record, 2.82 ERA, 0.97 WHIP, and 89 strikeouts in 73.1 innings, demonstrating elite strikeout ability and command across his four‑pitch mix.
A cautious workload limited his counting stats, but if stretched out in 2026, he could deliver mid-rotation ratios with strong strikeout totals, making him an under-drafted pitcher with significant upside.
Miami Marlins OF Jakob Marsee: Rank 27, ADP 146
Jakob Marsee is a 2026 fantasy sleeper after an impressive rookie season with the Miami Marlins in 2025, where he hit .292 with 5 HR, 33 RBI, 28 runs, 14 stolen bases, a .363 OBP, and .842 OPS in just 55 games.
Even in a limited sample, he showcased a rare power-speed combination paired with strong plate discipline.
Projections see him hitting near the top of the order in 2026, with the potential for 15+ home runs, 50+ stolen bases, 90 runs, and 60+ RBI, giving him multi-category upside at a low draft cost and making him a true sleeper.
Cincinnati Reds 1B Sal Stewart: Rank 18, ADP 208
Sal Stewart is a 2026 fantasy sleeper whose 2025 MLB debut hinted at significant upside. After dominating the minors (.309/.383/.524 with 20 HR and 17 SB), he slashed .255/.291/.545 with 5 HR, 8 RBI, and 11 runs in 18 MLB games, showing power and hard-hit ability in a limited sample.
Projections suggest 20+ home runs and solid counting stats if he earns regular at-bats in 2026, especially in a hitter-friendly park.
Under the radar in many drafts, Stewart offers late-round multi-category upside, making him a classic sleeper.
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Ryan Shea is a seasoned sports enthusiast with a sharp eye for strategy and a deep love for the game—no matter the sport. Whether he’s analyzing roster moves or spotting trends before they hit the headlines, Ryan brings a unique mix of research, instinct, and insider perspective to his writing. With over a decade of experience dominating fantasy leagues, he knows what it takes to build championship-caliber lineups. A diehard fan of all things New York, Ryan proudly reps the Jets, Yankees, Knicks, and Rangers—win or lose.