10 Fantasy Baseball Prospect Breakouts: Rookie Risers With Big Upside

March 12, 2026

Andy's top 2026 fantasy baseball prospects breakouts, sleepers, risers with big upside to target. These fantasy baseball rookie call-ups could win leagues.

Every season, fantasy managers see top prospects reach the major leagues and make an immediate impact in fantasy baseball. Last season, some of the top prospect performers were Logan Henderson, Daylen Lile, and Nick Kurtz.

In this piece, we will spotlight 10 more high-upside prospects who may not only be in the majors to begin the season but also have the skill set to make a major impact.

Who are 10 high-impact fantasy baseball prospects managers should keep on their radar heading into draft season? Let's dive in!

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Nolan McLean, SP, New York Mets

Current Level: MLB
2025 MLB stats: 48 IP, 2.06 ERA, 1.04 WHIP, 57 SO, 16 BB

New York Mets right-handed pitching prospect Nolan McLean was dominant in his Grapefruit League debut against the Houston Astros, allowing no runs on one hit, one walk, and six strikeouts in four innings pitched, according to MLB Pipeline. The No. 6 overall prospect in all of baseball picked up where he left off after posting a 2.06 ERA in eight starts for the Mets last year in his MLB debut.

McLean retired 12 of the 14 batters he faced on the day and topped out at 97.9 mph on the radar gun with his fastball. The 24-year-old former third-rounder in 2023 out of Oklahoma State University should be considered a top-100 overall fantasy player going into his first full year in the big leagues. In addition to his 2.06 ERA in New York in 2025, McLean had a 1.04 WHIP, 57 strikeouts, 16 walks, and a 61.1% ground-ball rate in 48 innings.

McLean already has an advanced arsenal with multiple offspeed pitches that can also generate swings and misses. He's one of the most attractive young arms in the game.

Andrew Painter, SP, Philadelphia Phillies

Current Level: MLB
2025 MiLB stats: 106 2/3 IP, 5.40 ERA, 1.55 WHIP, 111 SO, 46 BB

Philadelphia Phillies starting pitcher Andrew Painter had a dominant first start of spring training and looks like he will be on the team's Opening Day roster, according to MLB Network's Jon Morosi. Painter threw two perfect innings against the Yankees last Sunday against the Yankees, throwing 20 pitches and getting a strikeout against Jasson Dominguez.

Andrew Painter gets his first #SpringTraining strikeout 🎨 pic.twitter.com/MRf2PuTKfB

— MLB (@MLB) March 1, 2026

The former top prospect struggled to a 5.40 ERA and 4.90 FIP in Triple-A last year, but he was able to throw 118 minor-league innings, a huge accomplishment after missing 2023 and 2024 with Tommy John surgery. If he continues to put together a strong spring, he will likely open the year in the rotation, and he could keep that spot over Taijuan Walker after Zack Wheeler's return if he can deliver on his elite potential.

Brice Matthews, INF/OF, Houston Astros

Current Level: Triple-A
2025 MiLB stats: 112 G, .260/.371/.458, 18 2B, 17 HR, 41 SB

Houston Astros shortstop/outfield prospect Brice Matthews has enjoyed a hot start to spring training and is making a strong case to earn a spot on the Opening Day roster. The team's top prospect (according to MLB.com) has gone 4-for-10 at the plate with one double and one stolen base. Matthews progressed through the minors as a shortstop but has begun to see time in the outfield, given Houston's immense infield depth.

Last summer, the former 28th overall pick made his MLB debut and held a .167/.222/.452 line with four home runs and one stolen base across a brief 13-game stint. He spent most of the summer at Triple-A Sugar Land, where he held a .260/.371/.458 line with 17 home runs and 41 swiped bases over a 112-game stint. Given Houston's lack of proven options in the outfield, Matthews could be worth a late-round selection given his power and speed upside.

Thomas White, SP, Miami Marlins

Current Level: Triple-A
2025 MiLB stats: 89 2/3 IP, 2.31 ERA, 1.18 WHIP, 145 SO, 51 BB

The Miami Marlins announced on Tuesday that they reassigned left-handed pitching prospect Thomas White (oblique) to minor-league camp. White was already not expected to open the 2026 regular season in Miami's big-league starting rotation, and that was confirmed when the 21-year-old was diagnosed with a strained oblique muscle in spring training. White will most likely start the year at Triple-A Jacksonville, but he could be one of the first options for an open rotation spot in Miami this year.

In three minor-league stops last year, White was impressive, going 4-3 with a 2.31 ERA and 1.18 WHIP with 145 strikeouts and 51 walks in 89 2/3 innings over 21 starts. The 6-foot-5 southpaw needs to improve his control, like many young pitchers, but if he does, White has top-of-the-rotation potential at the big-league level.

Jett Williams, INF, Milwaukee Brewers

Current Level: Triple-A
2025 MiLB stats: 130 G, .261/.363/.465, 34 2B, 17 HR, 34 SB

Milwaukee Brewers infield prospect Jett Williams (quadriceps) is dealing with left quad soreness. He sustained this injury during last week's spring training contest. The young infielder has been held out of action since then. However, Brewers manager Pat Murphy noted that the injury is a "2 out of 10" on the severity scale, which suggests the infielder should be back in action in the coming days.

The Brewers acquired Williams from the New York Mets as the headliner piece in the deal that sent right-handed pitcher Freddy Peralta to Queens earlier in the winter. Williams is in the mix to compete for a starting role out of spring training, but will likely be sent to Triple-A to open the 2026 season. Last summer, Williams struggled over his first 36 games at Triple-A, holding a .209/.285/.433 line.

He remains a viable early-season stash target in deeper 12+ team formats.

Bubba Chandler, SP, Pittsburgh Pirates

Current Level: Triple-A
2025 MLB stats: 31 1/3 IP, 4.02 ERA, 0.93 WHIP, 31 SO, 4 BB

Pittsburgh Pirates right-handed pitching prospect Bubba Chandler stumbled in his second outing of spring training on Sunday afternoon. The top pitching prospect entered the game in relief behind Braxton Ashcraft and struggled, tossing 1 1/3 innings of two-run ball. In this brief appearance, Chandler allowed a high three walks with only two strikeouts. Chandler has now logged three innings in the spring with six earned runs and a modest 4:7 K:BB.

Last summer, Chandler struggled with his command at Triple-A, which kept him in the minor leagues for most of the season.

However, in the majors, Chandler looked far more comfortable, allowing only four total free passes over 31 2/3 innings. Managers should continue to keep a close eye on his progression in camp. While he remains locked into a starring role, Chandler could see his upside significantly capped due to his inconsistent command.

First MLB strikeout for Bubba Chandler 👏 pic.twitter.com/hrzjOZoYCG

— Pittsburgh Pirates (@Pirates) August 23, 2025

Spencer Jones, OF, New York Yankees

Current Level: Triple-A
2025 MiLB stats: 116 G, .274/.362/.571, 23 2B, 35 HR, 29 SB

The New York Yankees announced on Monday that they sent outfield prospect Spencer Jones and right-hander Elmer Rodriguez to minor-league camp. Despite looking good at the plate in Grapefruit League games -- Jones went 6-for-18 with three home runs and three stolen bases in spring training -- the 24-year-old left-handed slugger will begin the 2026 season at Triple-A Scranton/Wilkes-Barre.

Even with Jasson Dominguez potentially starting the year in the minors, too, there isn't room for Jones on the big-league roster just yet.

Making contact more consistently continues to be the focus for Jones, who struck out 36.6% of the time at Triple-A in 2025. He hit .274/.362/.571 with a .932 OPS, 35 home runs, 80 RBI, 102 runs scored, and 29 steals in 116 games at Triple-A and Double-A Somerset last year. Jones' plus-plus power and plus speed will eventually play at the major-league level, but he could be a serious drain on your batting average if he doesn't clean up his plate discipline and make more contact.

Jonah Tong, SP, New York Mets

Current Level: Triple-A
2025 MLB stats: 18 2/3 IP, 7.71 ERA, 1.77 WHIP, 22 SO, 9 BB

The New York Mets announced on Tuesday that they optioned right-hander Jonah Tong to Triple-A Syracuse. Tong will most likely be back in the big leagues with the Mets at some point in 2026, but for now, he'll get some more seasoning in the minors to begin the year. The 22-year-old gave up three runs in 2 2/3 innings in his lone Grapefruit League start this spring. The Canadian hurler and former seventh-round pick in 2022 also struggled in his major-league debut last season, posting a 7.71 ERA and 1.77 WHIP with 22 strikeouts and nine walks in 18 2/3 innings over his first five starts for the Mets.

It shouldn't take away from how great he was in the minors in 2025, as he posted a 1.43 ERA, 0.92 WHIP, 179 strikeouts, and a 52.9% ground-ball rate in 22 starts at Double-A and Triple-A. Tong will eventually be locked into a starting rotation spot for the Mets down the road, but there are durability questions because of his small stature of 6-foot-1 and 180 pounds.

Parker Messick, SP, Cleveland Guardians

Current Level: Triple-A
2025 MLB stats: 39 2/3 IP, 2.72 ERA, 1.31 WHIP, 38 SO, 6 BB

Cleveland Guardians left-handed pitching prospect Parker Messick logged another strong outing on Monday afternoon and continues to make a strong case to begin the campaign in the starting rotation. Messick logged 4 2/3 innings against the Kansas City Royals and allowed no runs with just two hits and one walk. He struck out four. Over his three appearances in camp (two starts), the young southpaw has tossed 9 1/3 innings to the tune of a 1.93 ERA, 1.07 WHIP, and a 7:4 K:BB.

He made his MLB debut late in the 2025 season and looked quite comfortable, posting a 2.72 ERA with a 1.31 WHIP over his first 39 2/3 innings. He is currently competing alongside Logan Allen and Joey Cantillo for one of the final starting positions. If he were to break camp in the rotation, he would have solid late-round sleeper appeal.

JJ Wetherholt, SS, St. Louis Cardinals

Current Level: Triple-A
2025 MiLB stats: 109 G, .306/.421/.510, 17 HR, 23 SB

St. Louis Cardinals top prospect JJ Wetherholt has continued to perform at a high level in the Grapefruit League as he launched his second home run on Monday afternoon against the Baltimore Orioles. Through nine games, Wetherholt has gone 5-for-18 with two long balls, one stolen base, and a strong 4:7 K:BB. The top shortstop appears to be a clear favorite to be in the team's Opening Day lineup, and his performance in spring training further supports this. According to MLB.com, the former seventh overall pick is considered the sport's No. 5 overall prospect.

HIS NAME IS JJ WETHERHOLT 🤘 pic.twitter.com/A3IxPeF1bE

— St. Louis Cardinals (@Cardinals) March 9, 2026

Last season, Wetherholt spent his campaign with Double-A and Triple-A and held an overall .306/.421/.510 line with 28 doubles, 17 home runs, and 23 stolen bases. Given his five-category profile and potential for everyday at-bats, Wetherholt is a top late-round breakout selection for all fantasy formats.

2026 Prospect Fantasy Baseball Rankings

Who are the top fantasy baseball prospects to know? Check out our latest 2026 prospect fantasy baseball rankings which are updated regularly:

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