Top 10 Fantasy Baseball Prospect Rankings: Third Basemen

These prospect rankings are based on fantasy baseball value, not real-life value. Considering such, hitters generally weigh a bit heavier for me due to the injury risk and higher volatility of prospect pitchers. Proximity to the Majors is also prominent in the equation, though these prospect fantasy baseball rankings are focused on long-term/dynasty outlooks. Think of these rankings as more of a five-year plan.

Rather than getting into writing mini-bios on all prospects, I’ve decided to keep my rankings simple by providing the 2024 and 2025 stats of each player across all levels, plus a player comp, a small blurb on their prime skills for fantasy and an explanation of my ranking.

I’ve also included updated fScores for any players I expect to debut in 2025 (some are updated from May, while others still feature preseason fScores), which highlights what my fScore projections believe the player is capable of at the pro level for immediate impact.

I know most people don’t care to read 250-500 words on each player, so using both box score scouting and film review, I have provided comps for each prospect. For fun, note that comps may be based on mechanics, body type, pitching arsenal or similar skills & box score style and how I think each prospect will perform once in the Majors over the next five seasons or so.

All-in-all, rankings paired with statistical info and a player comp will hit the sweet spot for the broadest category of people reading these prospect fantasy baseball rankings (or listening/watching the Fantasy Aceball podcast).

NOTE: Rookie status is determined by 130 at-bats or 50 innings pitched at the Major League level.

Full Top 150 Prospect Rankings:

Updated Positional Prospect Rankings:

Top 10 Fantasy Baseball Prospect Rankings: Third Basemen

1. Luis Pena (SS, 3B – MIL)

• 2024 DSL: .393/.457/.583 | 8.2 BB%, 8.2 K% | 23 XBH, 1 HR, 39 SB
• 2025 A (as of June 30, 2025): .315/.380/.502 | 8.7 BB%, 13.1 K% | 21 XBH, 6 HR, 33 SB
• Age: 18
• ETA: 2027
• fScores: N/A
• Comp: Righty Francisco Lindor mechanics meet Jacob Wilson‘s plate approach with speed
• Prime Skills: Luis Pena has a plus hit tool with an 82.4% contact rate and is rocking a 106.5 90th percentile exit velocity this season, which is higher than his 104 max exit velocity last season in the Dominican Summer League (DSL). The plate skills are reminiscent of Franklin Arias, but he’s a year behind him in development.
• Ranking Explanation: Third base is a weak position from a prospect standpoint, but one must remember that a lot of shortstops are likely to move off and over to third base. Pena will likely be bumped from shortstop, but then the question is where to. Brock Wilken is also a third baseman and may move to first base. Pena has the best hit tool and the highest fantasy upside of any of these players by a pretty wide margin.
• Top 150 Ranking: 28

2. Caleb Bonemer (SS, 3B – CWS)

• 2025 A (as of 6/30/25): .263/.394/.408 | 16.6 BB%, 22.8 K% | 20 XBH, 5 HR, 20 SB
• Age: 19
• ETA: 2027
• fScores: N/A
• Comp: Bobby Witt Jr.-lite
• Prime Skills: Caleb Bonemar has great bat speed with an insane eye for his age. He is a well-built shortstop who may end up moving to third base with plus tools across the board. Bonemer has a quick, powerful swing that reminds me of Bobby Witt Jr. He was one of the high-end prep bats picked in the second round last season.
• Ranking Explanation: Bonemer will likely end up at third base if Colson Montgomery pans out. He has lefties figured out, but has been only average against righties. The contact rate is down a few points since my last rankings update, and I would like to see more power. Ultimately, we have a 55 hit tool, 60 plate approach and 55 power guy who knows how to steal some bags. Bonemer has a higher power potential than Pena and will walk more, but Pena has an elite hit tool and gets the edge.
• Top 150 Ranking: 40

3. Brock Wilken (3B – MIL)

• 2024 AA: .200/.314/.365 | 13.3 BB%, 28 K% | 33 XBH, 17 HR, 1 SB
• 2025 AA (as of June 30, 2025): .230/.392/.550 | 20.1 BB%, 26.1 K% | 35 XBH, 18 HR, 2 SB
• Age: 22
• ETA: Early 2026
• fScores: 87 fContact, 119 fDiscipline, 113 fPower, 72 fSpeed
• Comp: Righty Max Muncy
• Prime Skills: Brock Wilken has massive power, but the question is if the hit tool can be average enough to allow him to mash 30-40 homers. His contact rate is up to 74%, which is good enough with his power, and he has a top-notch eye. He’s been making nice strides post-injury this season.
• Ranking Explanation: Wilken missed time in 2024 after getting hit in the eye with a pitch, and it messed up his entire season. Don’t get too excited about his low average this year either, as he’s been hitting in the Southern League, which is the opposite Minor League version of the Pacific Coast League — that, or the Low-A Florida State League (FSL). He’s also running a ridiculously unlucky .234 batting average on balls in play (BABIP), but the wRC+ is 165. Wilken has been ripping from a power standpoint and has the best power of all the guys in this group.
• Top 150 Ranking: 88

4. Sal Stewart (2B, 3B – CIN)

• 2024 A+: .279/.391/.454 | 14.8 BB%, 16.9 K% | 32 XBH, 8 HR, 10 SB (80 games)
• 2025 AA (as of June 30, 2025): .327/.390/.498 | 7.5 BB%, 16.1 K% | 27 XBH, 9 HR, 13 SB
• Age: 21
• ETA: Mid 2026
• fScores: N/A
• Comp: Spencer Steer/Nick Castellanos mash-up with Juan Yepez mechanics
• Prime Skills: Sal Stewart is a big dude who should develop more power. He has a fantastic plate approach and hit tool for his age. He might end up moving off the position because of his size. He has a good hit tool (81% contact rate), great plate skills and low 20s home run power potential.
• Ranking Explanation: Stewart is a bigger dude, and I don’t see him stealing more than 10-15 bags in the Majors when he’s young, just as I don’t see him play second base despite him leaning out. He’s a nice, well-rounded player with above-average tools, but I’m not sure if he has an upper-level player in him, though I bet he will be a solid buy for points leagues. Stewart is very solid, probably with an All-Star ceiling, but I don’t see a future fantasy super stud here.
• Top 150 Ranking: 83

5. Emil Morales (SS,3B – LAD)

• 2024 DSL: .342/.478/.691 | 19.9 BB%, 22.4 K% | 25 XBH, 14 HR, 12 SB (46 games)
• 2025 CPX (as of June 30, 2025): .301/.378/.509 | 10.2 BB%, 28.6 K% | 19 XBH, 7 HR, 4 SB
• Age: 18
• ETA: 2028
• fScores: N/A
• Comp: Fernando Tatis Jr.-lite
• Prime Skills: Emil Morales is a big, athletic shortstop with high-end power potential and decent speed. He has the Fernando Tatis Jr. swing, which has led to a similar batted ball profile (though beware of the high swinging strike rate). However, the profile has not been the same this year in the Florida Complex League (CPX) after a killer year in the DSL.
• Ranking Explanation: I’m hard pressed to rank CPX players this high, but Morales has electric fantasy potential as long as he can increase the contact rate — 61.7% is not good, but there’s room for improvement, especially if he keeps crushing the ball. He has a higher ceiling than Stewart, but Stewart has a ridiculously high floor and gets a slight nod since Morales is still down in the CPX..
• Top 150 Ranking: 81

6. Tommy White (1B, 3B – ATH)

• 2024 College: .330/.401/.638 | 8.6 BB%, 12.1 K% | 37 XBH, 24 HR, 3 SB
• 2024 A: .224/.303/.299 | 7.6 BB%, 17.6 K% | 4 XBH, 2 HR, 0 SB
• 2025 A+ (as of June 30, 2025): .277/.348/.505 | 8.6 BB%, 11.9 K% | 25 XBH, 9 HR, 2 SB
• Age: 22
• ETA: Mid 2026
• fScores: N/A
• Comp: Nolan Arenado-lite as a hitter
• Prime Skills: Tommy White was a great college hitter, and the thought that he wouldn’t be a great Major League hitter in retrospect is funny. White has an elite 85.4% contact rate this year with only a 7.3% SwStr%, while mashing to a 154 wRC+.
• Ranking Explanation: White is a free swinger who makes good contact and will put a ton of balls in play, which means he will be a great middle of the order RBI guy as long as he can keep the ball off the ground. He’s a corner infielder who is not known for his defense, so where he plays positionally will matter as the Athletics have a ton of first-base types. Third base or left field will be his best route to playing time with Nick Kurtz and Tyler Soderstrom already on the team. White has a higher power potential than Thomas Saggese and a better chance to be a starting regular, while Saggese might be a super utility type. Morales has a much higher fantasy upside, though, in shallow leagues, so I give him the nod.
• Top 150 Ranking: 110

7. Thomas Saggese (2B, SS,3B – STL)

• 2024 AAA: .253/.313/.438 | 5.9 BB%, 23.1 K% | 46 XBH, 20 HR, 9 SB
• 2024 MLB: .204/.250/.306 | 3.8 BB%, 26.9 K% | 3 XBH, 1 HR, 0 SB
• 2025 AAA: .317/.402/.445 | 12.2 BB%, 23.8 K% | 11 XBH, 5 HR, 5 SB
• 2025 MLB (as of June 30, 2025): .258/.277/.371 | 3.1 BB%, 23.1 K% | 5 XBH, 1 HR, 0 SB
• Age: 22
• ETA: Debuted
• fScores: 100 fContact, 86 fDiscipline, 89 fPower, 86 fSpeed
• Comp: Righty Matt Carpenter with more speed
• Prime Skills: Thomas Saggese has a good hit tool, very solid plate skills (which he showed off better in the Fall League than the iffy AAA season this year with 16 walks and only 15 strikeouts in the Fall League) and underrated power and speed for a guy that plays multiple infield positions. He’s kind of a jack of all trades and oddly has a reverse split against lefty pitchers at AAA this season. The hit tool has not been good at AAA (71.2% contact rate and 77.9% Z-contact%) this season.
• Ranking Explanation: He won’t be a superstar, but he should be a very valuable deeper league asset sooner, rather than later. He’s going to provide stats in all categories and will be great for points leagues. Saggese was hot in AAA before getting called back up to the Majors, where he has struggled a bit due to inconsistent playing time.
• Top 150 Ranking: 104

8. Seaver King (SS, 3B – WSH)

• 2024 College: .308/.377/.577 | 33 XBH, 16 HR, 11 SB
• 2024 A: .295/.367/.385 | 10 BB%, 14.4 K% | 4 XBH, 0 HR, 10 SB
• 2025 A+ (as of June 30, 2025): .249/.293/.357 | 5 BB%, 21.7 K% | 17 XBH, 5 HR, 14 SB
• Age: 22
• ETA: Mid 2026
• fScores: N/A
• Comp: Trea Turner-lite
• Prime Skills: Seaver King has a good hit tool and electric speed. King has a wide open stance that generates more power from his smaller frame than you would expect, which will likely translate more for doubles than homers in the Majors. He is aggressive in the zone and should run high averages (78.8% contact rate).
• Ranking Explanation: King has a high-end profile rating above average across the board in the hit tool, plate skills and power department with plus-plus speed. I expect him to have a killer year in High-A and AA, priming himself for a 2026 debut. King needs to work on taking some more walks and increasing his hard-hit rate. He has a decent amount of upside as the batting average should be better, considering he has a plus hit tool.
• Top 150 Ranking: 121

9. Jacob Reimer (2B – NYM)

• 2024 CPX/A/A+: .218/.358/.282 | 15.8 BB%, 14.7 K% | 5 XBH, 0 HR, 0 SB
• 2025 A+ (as of June 30, 2025): .281/.380/.494 | 11.3 BB%, 20.9 K% | 31 XBH, 9 HR, 11 SB
• Age: 21
• ETA: 2027
• fScores: N/A
• Comp: Justin Turner/Connor Norby mash-up
• Prime Skills: Jacob Reimer is a 6-foot-0, 205-pound third baseman who has always had a good eye through the Minors, almost like a Mark Canha. However, he has shown a solid 80.2% contact rate this year for a plus hit tool, and though we don’t have exit velocity numbers for him, a 28.2% line drive rate combined with a 49.3% pull rate has turned him into a weapon.
• Ranking Explanation: Reimer missed most of 2024 with a hamstring injury, and I literally had no idea who he was until this year, despite him having some prospect pedigree as a former fourth-rounder. Reimer has slowed down a bit through June, but overall has a solid contact profile with some plus gap power.
• Top 150 Ranking: 140

10. Brady House (3B – WSH)

• 2024 AA/AAA: .241/.297/.402 | 5.7 BB%, 26.4 K% | 41 XBH, 19 HR, 6 SB
• 2025 AAA: .304/.353/.519 | 7.1 BB%, 26.5 K% | 29 XBH, 13 HR, 0 SB
• 2025 MLB (as of June 30, 2025): .231/.268/.288 | 5.4 BB%, 25 K% | 3 XBH, 0 HR, 2 SB
• Age: 22
• ETA: Mid 2025
• fScores: 92 fContact, 48 fDiscipline, 79 fPower, 82 fSpeed
• Comp: Alec Bohm with worse plate skills
• Prime Skills: Brady House has a big frame with room to grow at 6-foot-44 and has completely moved off shortstop to third base this season. He has shown a ton of improvement in his plate skills and has a ton of power potential that has yet to play out. He is pretty good at going the other way. He reminds me a ton of Austin Riley coming up, where everyone liked him, then nobody liked him and then everyone liked him again.
• Ranking Explanation: House was one of the bigger fallers in my prospect rankings over the last couple of years, but he did rebound for a very nice AAA season before his call-up, showing a ton of power. However, his short Major League stint so far has not been good as he’s rocking a 41.3% chase rate and a terrible 2.6% barrel rate. He’s pressing and may not be up for the long haul at this point.
• Top 150 Ranking: N/A

Runners Up

11. Eric Bitonti (SS, 3B – MIL)
12. Mikey Romero (3B – BOS)
13. Brayden Taylor(2B, 3B – TB)
14. Kyle Karros (3B – COL)
15. Tai Peete (3B – TB)

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