5 Infield Fantasy Baseball Prospects to Stash in Dynasty and Keeper Leagues (2026)

December 15, 2025

Jamie looks at five Infield dynasty fantasy baseball prospects who are set to breakout in 2026. These players should be stashed in dynasty and keeper leagues: Kaelen Culpepper, Deyvison De Los Santos, Tommy White, more.

Preparation for the 2026 fantasy season is already underway. Drafts are happening, and we're getting a clearer picture of what to expect with players' ADP (Average Draft Position). However, managers in keeper and dynasty formats will have to take a different approach to prepare for their leagues.

Some managers may be in their competing window and looking to secure the championship this summer. By comparison, some managers will use the season to rebuild and retool their teams by acquiring budding prospects before they break out. Nonetheless, being able to add some players set to help you later in the season and beyond can go a long way to helping you achieve your targets.

Here, we'll be looking at five infield prospects who are unlikely to be taken in most redraft leagues but should still help fantasy teams in 2026. They make ideal targets for dynasty and keeper leagues as stashes for later in the year. Don't forget to follow the RotoBaller team for all your offseason news and articles.

Kaelen Culpepper, Minnesota Twins

Walker Jenkins and Emmanuel Rodriguez headline the Twins' farm system. But in Culpepper, their 2024 first-round draft pick, the Twins have a potential star. And one we may see in the majors at some point in 2026.

Culpepper impressed in his first full season as a professional. In 2025, he played 113 games across High-A and Double-A. Culpepper hit .289/.375/.469 with 20 homers and 25 stolen bases in the 113 games. He finished the year as the Twins' Minor League Player of the Year.

🏆Our 2025 @Twins Minor League Player & Pitcher of the Year🏆

Kaelen Culpepper & Connor Prielipp @Twins | #MNTwins pic.twitter.com/xOGlm6yi0a

— Twins Player Development (@TwinsPlayerDev) September 26, 2025

When the Twins drafted Culpepper, there was an assumption that he wouldn't be able to stick at shortstop. Culpepper was able to allay some concerns this year. His defense was excellent, and Culpepper looked like he could be a Major League shortstop for years to come.

There were also concerns that although Culpepper has plenty of pop, he'd strike out too much to maximize his powerful swing. Culpepper finished the year with a 17.4% K%. While that's nothing to get too excited about, it's still a solid number for a 22-year-old in his first pro season.

The one thing prospects also need is opportunity. With the Twins, Culpepper should get an opportunity. Minnesota has been trimming its payroll after moving multiple players at the trade deadline. They will be looking at their farm system to fill their roster over the coming months.

Culpepper likely won't start the season in the majors (he's not currently on the 40-man roster). If he starts 2026 as he performed in 2025, the Twins might look for Culpepper to add an in-season spark. Or at least give him a chance to adapt to the majors, with 2027 in mind.

Culpepper's combination of power and speed makes him a potential 20/20 player at the MLB level. He achieved that feat in his first full professional season and makes a nice stash option for fantasy managers looking to the future beyond next year.

Deyvison De Los Santos, Miami Marlins

De Los Santos rose to prominence in 2024 when he hit 40 home runs in the minor leagues. During that season, he was part of the A.J. Puk trade, going from the Diamondbacks to the Marlins. There was optimism that De Los Santos could find himself in the majors this year.

However, the Marlins didn't promote him, and De Los Santos didn't have the same impact in the minors. He played 106 games at Triple-A and only hit 12 home runs. After putting up a .294/.343/.571 slash line in 2024, De Los Santos only hit .241/.311/.363 at Triple-A this year.

The other issue holding De Los Santos back is his defense. He's a first baseman, and a below-average one at that, making 11 errors at first base in 2025. The good news is that the Marlins don't have anyone locked into first base and have been lacking much power in their lineup for some time.

Agustin Ramirez will continue mixing in at Designated Hitter (DH) when he doesn't catch, which doesn't help De Los Santos' chances of being an everyday player. De Los Santos also lacks discipline at the plate, swinging at almost everything.

It may sound like De Los Santos isn't worth a second thought, given the issues. But, there's still hope. He cut his strikeouts down this year, with a 22.3% K% (24.7% in 2024). De Los Santos also upped his walk rate, from 5.8% in 2024 to 8.1% in 2025.

Those numbers aren't great, but they show growth. And De Los Santos really cut down on swinging at pitches outside of the zone. After putting up a 45.6% O-Swing% in 2024 (percentage of pitches swung at outside of the strike zone), De Los Santos had a 34.5% O-Swing% in 2025.

The home runs did drop this year, but De Los Santos still hit the ball hard. His Hard-Hit% was 43.9% and De Los Santos had a maximum exit velocity of 118.5 MPH. When De Los Santos makes contact, the ball generally goes a long way.

There's still too much swing and miss in De Los Santos' profile to be an effective major leaguer. But he showed some areas of growth in his plate discipline this year. If he can continue that trend while returning to nearer his 2024 power numbers, De Los Santos could turn heads once again in 2026.

Gino Groover, Arizona Diamondbacks

LuJames "Gino" Groover might not be a name many are aware of. His minor league performances suggest he should be. Groover impressed in 21 minor league games after being drafted in 2023, hitting .283/.348/.394 with an 8.9% K%. Groover's 2024 season was interrupted by a wrist injury, costing him three months.

Groover still impressed. In 61 games across High-A and Double-A, he hit .281/.367/.474 with 10 homers. His strikeouts did increase, with a 13.6% K%. But so did the walks, with Groover having an 11.4% BB%. Groover then proved he can put up similar numbers over a full season.

He stayed healthy and played 123 games this year, all at Double-A. Groover had a .309/.399/.434 slash line with 12 homers, a 14.4% K%, and 11.5% BB%. There's also an opportunity looming for Groover to make his major league debut in the 2026 season.

The Diamondbacks traded away Eugenio Suarez last season and Jordan Lawlar is slated to be the third baseman in Arizona. However, he has struggled in two short spells in the majors, and Lawlar could see time in the outfield, as he was utilized there in the Dominican Winter League.

There have been stories coming out about Ketel Marte possibly being traded this offseason. That would open a spot at second base, which either Lawlar or Groover could fill. With Groover being utilized (and regarded) as a utility infielder, there are routes for him to make the Diamondbacks roster at some point.

"The Diamondbacks are actively listening."@jonmorosi has the latest on Ketel Marte potentially being traded this offseason 👀 pic.twitter.com/hjlD93EdqW

— MLB Network (@MLBNetwork) November 25, 2025

Groover doesn't have much power, but still enough not to be discounted. He's proven to be a solid all-around hitter in the minors and profiles as someone potentially more valuable in points leagues. That's not to say he shouldn't be on the radar of all dynasty and keeper league managers.

Tommy White, Athletics

The Athletics have gone about building a young and intriguing team and farm system as they prepare for their move to Las Vegas. White might not be one of the most exciting names, but he could still have a significant impact on the team next year and in future seasons. That's down to his power potential.

On the 20-80 scouting scale, White has an almost universal 60 grade for power. In real terms, that means he has plus power. It's something he demonstrated in College, hitting 75 homers in 187 games across three seasons, but has yet to really show as a pro.

This year was White's first full season in the minor leagues. He hit 12 home runs in 93 games across High-A and Double-A. White also had a robust .275/.334/.439 slash line with a solid 13.7% K% and 7.3% BB%. White showed enough power to take part in the Arizona Fall League Home Run Derby.

Channeling his inner tiger 🐅

2024 draft pick out of @LSUbaseball, Tommy White, hits 7 home runs in an electric first round of the Arizona Fall League Home Run Derby. pic.twitter.com/Bts5PQ0cSg

— MLB's Arizona Fall League (@MLBazFallLeague) November 9, 2025

The problem White has is opportunity. Or the potential lack of it. White is not a good defensive player, and while he's been playing at third base, he's more likely to be a first baseman moving forward. And he's not going to play in front of Nick Kurtz or DH ahead of Brent Rooker.

White will need to improve at third base if he is to have a clearer route to the majors. That's not impossible. If he can achieve that next year, White could find himself playing in the second-best hitters park (according to Statcast Park Factors).

White has already shown he's a capable hitter, and it shouldn't come as a shock if White were to demonstrate the sort of power that led to the Athletics using a second-round pick on him. If he does that to start 2026, he could end the year hitting homers for the Athletics.

Sam Antonacci, Chicago White Sox

As we did with the outfielders article, we're finishing with a White Sox player for one main reason — his speed. Antonacci stole 27 bases in 64 games at High-A. He then went on to steal 21 bases in 49 games at Double-A. It's hard to ignore 48 steals in 116 games. But there is more to Antonacci's game than just the steals.

Across the two levels, Antonacci hit .291/.433/.409. As you may be able to tell, there's little power in Antonacci's profile, with just five homers in 2025. The stolen bases were aided by Antonacci's ability to get on base, evidenced by his 13.3% BB%.

Antonacci also doesn't strike out much. He had a 14.1% K% this year, only striking out four more times than he walked. A significant reason for his stolen base total was his aggressive approach on the bases. Antonacci was regarded as having very good instincts, which should help him in the majors.

Those instincts and athleticism were on full display following his walk-off sacrifice fly in the Arizona Fall League Fall Stars Game earlier in November.

Antonacci still has to reach the majors, of course, to show off those instincts. Being in the White Sox organisation offers as good a chance as any to do that. What will help Antonacci is his versatility on the infield.

He predominantly played second base but also played third base and shortstop. His arm will probably keep Antonacci at second base as he develops, but the White Sox could have an opening at third base or second base moving forward.

Miguel Vargas and Chase Meidroth had decent seasons in 2025, but neither reached a point where they could be considered undroppable. Both are still young and inexperienced enough to believe they can kick on in 2026. Even if they do, Antonacci will be knocking on the door of the majors if he can replicate his 2025 numbers.

If your roster lacks some speed and there aren't many options available to you, Antonacci is well worth consideration for stashing. He won't provide much (if any) power. But given the chance, Antonacci should get on base plenty enough to maximise his speed and base running instincts.

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