Last Updated on December 14, 2018 by Jason A. Churchill

After the trades of Mike Zunino, James Paxton, James Pazos, Edwin Diaz and Robinson Cano, the Seattle Mariners have greatly improved their farm system.

Here’s a quick look at the Top 15 Prospect Rankings as of December 13, 2018. Players in bold acquired after the 2018 season. Player in italics acquired in the last 365 days.

1 Justus Sheffield LHP 22 FB
2 Jarred Kelenic CF 20 HIT
3 Julio Rodriguez RF 17 POWER
4 Justin Dunn RHP 23 FB
5 Kyle Lewis CF 23 POWER
6 Logan Gilbert RHP 21 FB
7 Evan White 1B 22 HIT
8 Noelvi Marte SS 16 POWER
9 Erik Swanson RHP 25 FB
10 Cal Raleigh C 21 POWER
11 Josh Stowers CF 21 HIT
12 Sam Carlson RHP 19 CH
13 Juan Querecuto SS 17 THROW
14 Dom Thompson-Williams CF 23 FIELD
15 Nick Rumbelow RHR 26 CB


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    Why is Kelenic listed as 20 when he’s 19 til July, and Rodriguez listed as 17 when he’s 18 tomorrow?

  2. Author

    Dipoto’s REAL WINDOW is going to start 2021-2022, but he will PR it for 2020.

    So there’s no point in trying to map put the roster right now. It’s at least, bare minimum, two years away. That player is not on the roster right now.

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    So who plays 2B when we hit Dipoto’s ‘window’?

  4. Author


    I think you’re correct regarding the roster not being terrible right now, although there is so little pitching top to bottom it would be toough to project more than 70-75 wins.

    As you alluded to, more changes are coming so we could be currently looking at 50% of the roster.

    I imagine I’ll be back to spending ample time in Tacoma this coming season as a result of the recent acquisitions. 🙂

  5. Author


    Bishop is one of the more overrated prospects in the system, generally speaking, but that isn’t his fault. It’s because the system has been so weak and he’s been called a Top-10 prospect — because he was in the worst farm system in baseball.

    At this stage I still have Bishop as a probable fourth outfielder with a slight chance to play a larger role but not a good chance to be a regular. He’s a plus runner and a plus-plus glove, but he isn’t going to hit for power, so there is a ton of pressure on the hit tool.

    He’s already 25 years old and won’t hit Triple-A — the toughest level in which to hit — until this spring. He’s a surefire major leaguer, but doesn’t have a great shot to play everyday for a decent team (often, platoon players and bench types play a lot for bad teams, but never would for a contender outside significant injury scenarios.)

    As of now, Bishop is 17-19 for me.

    As for Rumbelow, there’s no more question about the stuff; he’s major-league ready NOW and while his role (middle reliever) is limited in value, so is Bishop’s part-time player profile, and he has performance obstacles to deal with, still.

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    I always look forward to your prospect rankings and now we have a farm that further merits attention. I hope to hear more content from your website this season!!
    I also think the mariners as currently constructed aren’t nearly as horrible as most people would suggest. The biggest weakness is the bullpen and we all know how volatile and unpredictable bullpens are these days.

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    My bigger question is where is Braden Bishop, I would think he would rank top 10 or minimum top 15 ahead of a 26 year old reliever like Rumbelow. I assume Festa, Mills, DeCarlo, Gerber, and Warren would pull up the rear of a top 20? Seems like those guys would all be a small step down from Bishop and Rumbelow doesnt feel much like a prospect anymore.

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    Thank you JAC. I look forward to you’re rankings and pieces every chance I get. Good stuff!

  9. Author

    Are you telling me Swanson can’t play CF?

    Ok, yeah, he can’t.


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    Great list, thanks for doing it. As an FYI you have Erik Swanson listed as a CF. Have not heard that Dipoto is going to Dee Gordon him, but, at this stage I am willing to believe most things with Dipoto.

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