Fantasy Baseball Prospect Risers - Rookies to Stash and Top Performers for Week 13 (2025)

Andy's fantasy baseball prospects sleepers and risers to know for Week 13 of 2025. He analyzes top MLB prospects and rookies to stash based on recent performances.

Welcome, RotoBallers, to my Week 13 edition of the top prospect performers. In this week's piece, we will look at two emerging bats at the Triple-A level who are quickly approaching their MLB debut. On the pitching side, we highlight a Tampa Bay right-hander who has some major league experience but has begun to take the next step in the minor leagues.

In this weekly column, we analyze the top prospect performances of the week and determine if their performances truly matter for fantasy baseball. Should fantasy managers be stashing these prospects?

Adding the right prospect can fill the missing piece on your roster and set you up for a fantasy championship. This fantasy baseball prospects weekly series will examine a few key players in the minor leagues and assess whether they have a path to fantasy stardom in 2025.

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C.J. Kayfus, 1B, Cleveland Guardians

Guardians No. 5 Prospect, Overall 100

C.J. Kayfus has been a fast riser within the Cleveland system after being selected with the 93rd overall pick in the 2023 MLB Draft out of Miami. Kayfus began his professional career shortly after the draft with Low-A and held a solid .271/.429/.542 line across 17 games.

In 2024, Kayfus began his season with High-A Lake County and continued to swing a hot bat. Through 40 games, the first baseman posted a stellar .338/.437/.538 salash line with 12 doubles, two triples, and seven home runs. During this stretch, he held an impressive 33:23 K:BB. He then earned a taste of Double-A in the second half.

Through his first 67 games in the upper levels of the minor leagues, Kayfus took a slight step back, posting a .263/.366/.470 line with 14 doubles and 10 long balls.

He began the 2025 campaign with Double-A Akron as expected. As Kayfus showed in 2024, he immediately took a step forward at the start of the season. During his second taste of Double-A action, the No. 5-ranked prospect in the system posted an impressive .364/.475/.591 line with 14:11 K:BB through 18 games. This start earned him an early promotion to Triple-A.

With Triple-A, Kayfus has continued to swing a hot bat and is quickly approaching his MLB debut. In his first 43 games with Triple-A Columbus, Kayfus has posted a .315/.383/.562 line with 11 doubles, four triples, seven long balls, and a 50:18 K:BB.

Does this performance truly matter?

Under the hood, Kayfus holds stellar metrics that suggest he is more than ready to join Cleveland. In 2024, Kayfus posted a 24.3% K rate, which was lowered by one point in 2025, despite facing tougher competition. He has also increased his wOBA by over 20 points (.438 (2025) - .410 (2024)) and raised his wRC+ from 159 to 172.

Currently, Carlos Santana holds down first base in the majors and does not appear to be in any danger of losing playing time, despite his .248/.342/.376 line. However, at DH, Kyle Manzardo has cooled down following his hot start and could open the door for Kayfus. Since May 21 (last 20 games), Manzardo has held a .169/.229/.262 line.

He has even begun to lose time to David Fry at the DH spot.

If Kayfus continues to produce at Triple-A, he will force their hand.

The @CleGuardians' C.J. Kayfus, who is slashing .339/.430/.558 this season, enters the Top 100 Prospects list after Agustín Ramírez graduates: https://t.co/KSn9yLGUz6 pic.twitter.com/TcjMSIclJR

— MLB Pipeline (@MLBPipeline) June 1, 2025

Verdict: Stash in 12+ team leagues

Owen Caissie, OF, Chicago Cubs

Cubs No. 3 Prospect, Overall 49

The Chicago Cubs outfield prospect has been one of the most productive hitters at Triple-A since the start of June and is making a strong case to join the MLB roster. Since June 1, Caissie has held a .354/.455/.6366 slash line with seven doubles, four home runs, 12 RBI, one stolen base, and a 121:10 K:BB (through 18 games).

Across 61 total games with Triple-A Iowa, Caissie has posted a .268/.372/.502 line with 17 doubles, two triples, and 11 home runs.

The former 45th overall pick spent the entire 2024 campaign with Triple-A Iowa and enjoyed a similar production, posting a slightly lower .278/.375/.472 line with 29 doubles and 19 round-trippers across 127 games.

Throughout his time in the Cubs' system, Caissie has typically spun an entire campaign at a level before earning a promotion at the start of the following season.

While he has been one of the most impressive hitters at Triple-A this season, does the Notre Dame Catholic SS product have a viable path to join Chicago in the second half?

Unfortunately, unlike Kayfus, Caissie has a near-impossible path without a significant injury occurring. Currently, the Cubs boast one of the best outfields in baseball, featuring gold-glover Ian Happ in left field, MVP candidate Pete Crow-Armstrong in center field, and superstar Kyle Tucker in right field.

What about DH? Well, former everyday right fielder Seiya Suzuki owns that role and is in no danger of losing any plate appearances.

As a result, Caissie will only get the call if one of those four suffers a significant injury. In addition, one injury may not even be enough, as fellow Triple-A teammate Moises Ballesteros could even make another call to the bigs before Caissie.

Even though he appears to be a budding star, Caissie will have to wait until 2026 to reach the majors.

Owen Caissie is absolutely destroying the baseball right now. Unfortunately there is just no room for him on the ML roster. Wonder how coveted he becomes at the deadline if he keeps this up

— David Kep (@Davey_Baseball) June 18, 2025

Verdict: Fast-rising dynasty asset, unlikely to debut in 2025

Joe Boyle, SP, Tampa Bay Rays

Not considered a prospect

Joey Boyle was acquired by the Rays in the offseason in a deal that sent Jeffrey Springs to the Athletics. Since Boyle has already logged 68 2/3 innings in the majors as of June 18, he is not "officially" a prospect. However, the right-hander logged 47 2/3 of those in 2024 and has yet to see a true extended opportunity.

In 2024, Boyle struggled with the Athletics, posting a hefty 6.42 ERA and a 1.72 WHIP. During this stretch, he struck out an impressive 56 batters but had very weak command, allowing walks at a massive 17.7% rate.

In the majors, there are certain teams that we should trust to not only "fix" pitchers but develop them into potent fantasy studs, and the Rays are one of them. Through 64 innings with Triple-A Durham this season, Boyle has been nothing short of dominant, posting a 1.83 ERA with a 0.95 WHIP. During this stretch, he struck out 81 batters while walking just 25.

Boyle has made one spot start in Tampa Bay and looked just as strong. On April 13, Boyle faced the Braves and tossed five innings of a two-run ball (both earned) with seven punchouts and two walks.

Joe Boyle, Wicked 91mph Slider. 🤢

6th K pic.twitter.com/ccxqGDFGbz

— Rob Friedman (@PitchingNinja) April 13, 2025

Can Boyle find a path to join Tampa Bay in the second half? Currently, the Rays have a five-man rotation. While each pitcher has struggled at times (except Drew Rasmussen), they all do not appear to be in any danger of losing their spot.

The No. 5 option, Zack Littell, posted a high 4.40 ERA over his first 47 innings but has rebounded well, holding a much lower 3.35 ERA over his last 45 2/3 frames.

Similar to Caissie, while Boyle has flashed immense upside and massive growth at Triple-A this season, the current depth chart in the big leagues is not doing him any favors. However, if the Rays remain in the Wild Card hunt, they could opt to deploy a six-man rotation later in the season to preserve their starters.

For the time being, Boyle is only worth a look in deeper leagues despite his incredible success with Durham.

Verdict: Stash in 12+ team leagues

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