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(Photo of Juan Then courtesy Eden Douglas/West Virginia Power)

As we work our way toward Jarred Kelenic, Logan Gilbert, Kyle Lewis, George Kirby and Julio Rodriguez, among others, let’s continue the countdown of the Top 50 Seattle Mariners Prospects entering the 2020 season.

Down the page here, you’ll find prospects 16-50, including the update after the Mariners lost No. 31 Ricardo Sanchez on waivers to the St. Louis Cardinals Thursday.

Here are Nos. 11-15 in reverse order:

To get the full scouting reports, including ETAs, comps,and tools grades, subscribe to Baseball Things right here.

15. Juan Then, RHS
HT: 6-1 WT: 185 BATS: R THROWS: R AGE: 20

Then originally signed with Seattle in July of 2016 and was traded with J.P. Sears to the New York Yankees in 2017. He was re-acquired last summer in exchange for DH Edwin Encarnacion.

Then was very good after the trade, making 10 appearances at Short-Season Everett and Class-A West Virginia at 19 years old.

He’s put up good weight since being traded away and now sits 91-93 mph and touches 95.  He also has a curveball and changeup, the latter of which is a better present offering.

He’s made progress using his lower half in his delivery and locates the fastball better to his glove side than away from lefties.

Then likely starts 2020 back in West Virginia.


14. Jose Siri, CF
HT: 6-2 WT: 180 BATS: R THROWS: R AGE: 24

Siri was claimed off waivers from the Cincinnati Reds February 3, 2020 and joins a strong group of good defensive center fielders.

He’s toolsy, including 70 speed and a 65 arm, and offers some promise in the power department thanks to good bat speed and strength.

He’s still learning to get to the power in games and he’s a bit aggressive early in counts, but he’s a great athlete — maybe the best on the system — and if he can get to his pull power with loft there’s a Melvin Upton profile here.

Siri likely spend lots of time in Triple-A, but he could see the bigs sometime in 2020.


13. Sam Carlson, RHS
HT: 6-4 WT: 205 BATS: R THROWS: R AGE: 21

Carlson has lost a lot of development time to injury having faced just 13 batter in pro ball — and none since 2017 — but the physical tools and raw stuff cannot be ignored.

The right-hander is an absolute beast with athleticism to burn and pre-Draft sat 91-94 mph with sink and plane, touching 95, and showing an average slider with shape and a changeup beyond his years.

He’s likely to face workload restrictions in 2020, of course, but there’s also a chance his role is non-traditional as the club gets him time and avoids risk.

He may be capable of facing Sally League hitters, but Seattle might be thinking a softer landing in the Arizona League, which means lots of time in Extended this spring to build up arm strength.


12. Brandon Williamson, LHS
HT: 6-6 WT: 215 BATS: L THROWS: R AGE: 22

Williams was the club’s second-round pick last June and sat 91-93 mph for me in three appearances, but touched 94 and has been up to 96 in the past.

He has two projectable breaking balls, the slider the best one at present. His changeup needs work if he’s going to max out his upside, but there’s a lot to like about the physical profile.

The southpaw could be headed for West Virginia — likely joining a number of other high-ranked pitching prospects.

11. Justin Dunn, RHS
HT: 6-2 WT: 205 BATS: R THROWS: R AGE: 24

Dunn hasn’t fallen as much as been passed up by those now ranked ahead of him, but I do have a little more concern about his future role than I did a year ago.

With a power approach, Dunn’s fastball is 91-95 mph with life up in the zone, but late in the year he sat mostly 91-93 and the slider flattened — both of which can be chalked up as fatigue. But Dunn’s changeup did not improve to the point where it yet projects as even big-league average, and that’s a problem.

If he ends up in the bullpen he could be 95-99 with a better slider than Edwin Diaz, but I’d like to see Dunn get 15-20 more chances, at least, to see if he can start long-term. Seattle is no hurry for the answer and banishing arms like Dunn’s to relief work this early is ridiculously shortsighted, which is why I don’t think Seattle makes the move just yet.


NO. PLAYER POS AGE BEST TOOL 2020 PROJ
50 Dutch Landis RHP 18 CH Arizona (R)
49 Ryne Inman RHP 24 CB Modesto (A+)
48 Gerson Bautista RHP 25 FB Tacoma (AAA)
47 Tim Elliott RHP 22 SL Modesto (A+)
46 Tyler Driver RHP 19 CB Everett (SS)
45 Elvis Alvardo RHP 21 FB Arizona (R)
44 Donnie Walton UT 26 RUN Tacoma (AAA)
43 Levi Stoudt RHP 22 CH Arizona (R)
42 Tim Lopes UT 25 RUN Seattle
41 Jorge Benitez LHP 21 SL West Virginia (A)
40 Dom Thompson-Williams OF 25 RUN Arkansas (AA)
39 Michael Limoncelli RHP 20 CB Arizona (R)
38 Danny Chang LHP 20 CB Everett (SS)
37 Adam Hill RHP 23 CH Modesto (A+)
36 Ty Adcock RHP 23 FB West Virginia (A)
35 Raymond Kerr LHP 25 FB Arkansas (AA)
34 Juan Querecuto SS 19 FIELD Arizona (R)
33 Jake Haberer RHP 25 FB Arkansas (AA)
32 Ljay Newsome RHP 23 CMD Arkansas (AA)
31 Carter Bins C 21 FIELD West Virginia (A)
30 Brayan Perez LHP 19 CB West Virginia (A)
29 Art Warren RHP 27 FB Seattle
28 Damon Casetta-Stubbs RHP 20 SL West Virginia (A)
27 Sam Delaplane RHP 25 CB Tacoma (AAA)
26 Jonatan Clase CF 17 RUN Arizona (R)
25 George Feliz CF 17 FIELD DSL (R)
24 Wyatt Mills RHP 25 FB Tacoma (AAA)
23 Yohan Ramirez RHP 25 FB Seattle
22 Aaron Fletcher LHP 24 FB Tacoma (AAA)
21 Joey Gerber RHP 23 FB Tacoma (AAA)
20 Austin Shenton 3B 22 HIT Modesto (A+)
19 Taylor Guilbeau LHP 25 FB Seattle
18 Braden Bishop CF 26 FIELD Seattle
17 Jake Fraley CF 25 HIT Seattle
16 Kristian Cardozo RHP 17 FB DSL (R)
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Jason A. Churchill

Churchill founded Prospect Insider in 2006 and spent several years covering prep, college and pro sports for various newspapers, including The News Tribune and Seattle PI. Jason spent 4 1/2 years at ESPN and two years at CBS Radio. Find Jason's baseball podcast, Baseball Things, right here.