2026 Seattle Mariners Top 30 Prospects Update

Team Outlook
It’s hard to come up with a prospect pitching duo in history that can rival what the Seattle Mariners have right now. Kade Anderson and Ryan Sloan both look like legitimate top of the rotation weapons. Even after graduating Colt Emerson, this system is still loaded at the top. Beyond the arms, Lazaro Montes, Felnin Celesten, Jonny Farmelo, and Michael Arroyo lead the way for a solid crop of hitting prospects. Ace Reese was their first round pick, and he settles inside the top 10 as well. It’s a talented big league club with a talented farm system. That is ideal.
About Our Top 30 Lists
Prospects Live, led by its evaluating team & Director of Scouting Trevor Hooth, is proud to begin updating and expanding system reports. The team combines industry feedback, our live looks, film, and available data to compile each org. We believe this effort has enabled us to present you, the reader, with our best possible view of the prospects in the organization.
We have constructed this list using the Overall Future Potential (OFP) scale. There is no perfect equation for ranking prospects or assigning value to them, but we believe this method is the best possible approach. Every prospect on this list has been graded based on the tried and true 20-80 scouting scale. An 80 is the highest tool and OFP grade on the scale, reserved for MVP-caliber players or tools. Conversely, a 20 is reserved for non-prospects (NPs). A 50 OFP falls in the middle, indicating our evaluators deem this player a future average major league player. Below the 50 OFP tier are the 45s and 40s, comprising a large majority of players on each list. These are specific-role players, such as platoon hitters, utility players, or low-leverage relievers. Above the 50 OFP tier are the 55s and 60s. A 55 represents a future above-average player, and a 60 OFP designation is reserved for future All-Star caliber players.
In addition to the tool grades and OFP, we will also include a ‘Risk’ associated with each prospect. We use this to better communicate to you, the reader, whether a grade is more aggressive or conservative in nature. The evaluation team has worked hard to apply both the grades and risk components to better illustrate how each individual prospect stacks up in their respective system and in the baseball ecosystem.
These lists include the most recent draft picks. The picks may not sign with the team, and that will be acknowledged, but for the time being we will include the picks. Should it come out that they are not signing with the organization, we will update the lists to reflect that. The PLive draft team worked hard to get writeups with grades for draft prospects, but because of the difference in level and team, the grades may not reflect their placement.
Evaluators: Matt Seese, Jacob Maxwell, Mitch Stachnik, Grant Carver, Danny Barrand, Drew Wheeler, Billy McMahan, JB Sebastiano, Nate Jones, Will Dodge, Gabriel Estevez, Brandon Tew, Trevor Hooth
Find all the previous Top 20 Lists, as well as the updated lists Top 30 as they release here:
2026 Team Prospect Lists – Prospects Live
Top 30 Prospects at a Glance
1. Kade Anderson, LHP – 60 OFP
2. Ryan Sloan, RHP – 60 OFP
3. Lazaro Montes, OF – 50 OFP
4. Felnin Celesten, SS – 50 OFP
5. Jonny Farmelo, OF – 50 OFP
6. Michael Arroyo, 2B – 50 OFP
7. Ace Reese, 3B – 55 OFP
8. Luke Stevenson, C – 50 OFP
9. Mason Peters, LHP – 50 OFP
10. Yorger Bautista, OF – 45 OFP
11. Nick Becker, SS – 45 OFP
12. Jake Brown, OF – 45 OFP
13. Juan Rijo, OF – 45 OFP
14. Gregory Pio, OF – 45 OFP
15. Nathan Taylor, RHP – 40 OFP
16. Korbyn Dickerson, OF – 45 OFP
17. Griffin Hugus, RHP – 40 OFP
18. Teddy McGraw, RHP – 45 OFP
19. Henry Ford, OF – 45 OFP
20. Po-Chun Lin, RHP – 45 OFP
21. Brock Rodden, 2B – 45 OFP
22. Colton Shaw, RHP – 40 OFP
23. Brock Moore, LHP – 45 OFP
24. Jackson Steensma, RHP – 45 OFP
25. Grant Knipp, RHP – 45 OFP
26. Charlie Beilenson, RHP – 40 OFP
27. Victor Labrada, CF – 40 OFP
28. Chia-Shi Shen, RHP – 40 OFP
29. Diego Contreras, 2B – 40 OFP
30. Leandro Romero, SS – 40 OFP
Scouting Reports
Find Scouting Reports and Tool Grades in each toggle section
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Kade Anderson, LHP – 60 OFP
HT: 6-2 WT: 179 H/T: L/L
Highest Level: AA
ETA: 2027
OFP: 60
Risk: Low
Fastball: 55 – (92-95 mph)
Curveball: 55 – (77-80 mph)
Slider: 55 – (84-86 mph)
Changeup: 55 – (82-84 mph)
Command: 55
Scouting Report
Kade Anderson was expected by many to be the first overall pick to the Nationals in last year’s draft. He posted one of the most dominant seasons in college baseball history in 2025 and is a projectable lefty with a deep mix of above-average pitches. The Mariners were happy to be selected in the top three to begin with, but had to be ecstatic when Anderson fell into their laps. Anderson is as safe a bet to stick as an above-average major league starter as there is in this class. He operates with an ultra-smooth, repeatable delivery from the left side and still has room to add strength, which could lead to a bump in velocity. Anderson features a polished four-pitch mix: fastball, slider, changeup, and curveball. The fastball averaged just over 93 mph in 2025 and generated a strong 37 percent whiff rate. With continued physical development, it’s easy to envision him ticking up into the 94–95 mph range consistently. Anderson’s slider is a standout offering. It was landed for a strike 71 percent of the time last year and was particularly effective against left-handed hitters, appearing as a strike before diving off the plate at the last second. It generated a 31 percent whiff rate and a 34 percent chase rate, with the whiff rate jumping all the way to 83 percent on pitches located out of the zone. Anderson actually posted reverse splits in 2025. Right-handed hitters managed just a .544 OPS against him, while lefties were over the .800 mark. The primary reason for his success against righties was the changeup, which I have as an above-average pitch despite some shape questions. He leaned on it heavily vs. RHH, and it delivered outlier numbers: a 51 percent whiff rate and a 49 percent chase rate. Rounding out the arsenal is a sharp curveball. While it was hit hard a few times when left in the middle of the zone, it’s another above-average to plus pitch. Ideally, you’d like to see more chase on it given its usage out of the zone, but the whiff numbers were still solid. There are no reliever concerns here. Anderson projects as a safe mid-rotation arm with the potential for more. The floor is a high-end 3 starter, and the upside could look something like a Max Fried. – Jacob Maxwell
Ryan Sloan, RHP – 60 OFP
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