It’s prospect ranking season and this week we kick off the Top 30 prospects in the Mariners system for 2020. A reminder that most other outlets are just getting started at the Top 30 but we’ve already cruised through 20 other names you should know, plus a bonus roundup of other interesting players. You can catch up on all that in the main hub here. Today we venture into the Top 30 with a group of arms who might not have a ton of buzz outside of the organization but whom we’re pretty excited to see in 2020.
30. RHP Devin Sweet
The Mariners had expressed interest in Sweet prior to the 2018 draft, but he didn’t hear his name called on draft day. Instead Sweet prepared to head to grad school at Virginia Tech, where he planned to study engineering, until he got a call that July in the middle of picking up a friend at the airport asking him to get on a plane himself. Sweet’s first 34 games in the system were played as a reliever, often in a multi-inning role. In 2018 he posted an ERA of 4.66 across three different levels in the organization, although with an impressive 24 strikeouts in just 19 innings. He opened again as a reliever with West Virginia in 2019, but after a spot opened in the rotation in mid-June, Sweet seized that role and didn’t look back, posting an ERA of 2.54 as a starter vs. 4.04 as a reliever. Sweet’s best pitch is a circle change he worked on with Mariners pitching coach Alon Leichman, himself the owner of an outstanding changeup, which has devastating late drop. It pairs well with his sinking fastball, to which Sweet has reportedly added a couple ticks after spending this off-season at Gas Camp, leading to a K% of almost 30% this season. He’s also been working on a slider that he’s been developing since the Mariners sent him to their Dominican Academy in the 2018 off-season to focus on the pitch. Sweet has good command and doesn’t walk batters; the next step will be to see if he can stick as a starter against more advanced hitters in Modesto and Arkansas. -KP
29. RHP Jack Anderson
Anderson isn’t a strikeout monster like fellow Arkansas Travelers Sam Delaplane, Art Warren, or Joey Gerber; where he shines is in inducing weak contact, averaging a groundball rate of almost 65% over his time in the minors. He also saw a pretty impressive record of his get broken this past year in Double-A, when Anderson allowed the first home run ever of his professional career. For someone with 200 career innings in the minors, that’s quite a record. Anderson is a true submarine pitcher who admits his knuckles will occasionally scrape the dirt, and hitters have a hard time picking up his sinking fastball or his true weapon, a slider that seems to rise on batters. Anderson needs to work on attacking righties, who averaged .275 off him last year, but he’s close to the bigs and might pop up in Seattle’s bullpen at some point this year, at which time you’ll probably see a lot of general excitement over his unorthodox delivery. -KP
28. LHP Taylor Guilbeau
A 10th round pick by the Washington Nationals in 2015, Guilbeau came to Seattle by way of the Roenis Elias trade. He’s a deceptive, hard-throwing lefty with a good sinker-changeup combo. Guilbeau featured an above average slider during his time in Washington, but since arriving to Seattle, he ditched the breaking ball as it’s command issues put the southpaw behind the 8-ball more often than not. Now primarily a two-pitch pitcher, Guilbeau throws a stiff 95 mph sinker with some arm-run. The changeup was devastating against righties last year, suggesting he should fare just fine with the new three-batter minimum. In fact, Guilbeau was actually more effective against right-handed hitters than he was lefties. Righties ran a slash of .200/.259/.320 while lefties slashed a more robust .227/.292/.455 in limited action. The walk rate will be the number to watch next season, as it was the primary reason he never pitched for the Nationals before being traded. He issued less free passes than his resume suggests he should last season with Seattle, so he’ll need to continue that trend to lockdown a long-term spot in the ‘pen. - JD
27. RHP Ljay Newsome
Ljay (pronunced “Ell-jay,” and not, as the Cubs announcers would have you believe, “L’jay”), has been in the Mariners organization longer than Nelson Cruz, Mike Cameron, or Adrian Beltré were. Sometimes players develop as expected, but oftentimes for guys like Newsome, the path is far more meandering. The small-framed righty has been on our radar since Kate’s profile in 2018, which includes an interesting tidbit on the player he was, versus who he has become. Newsome noted in 2018 his effort to keep the ball down - a commonly taught ethos that logically tracks against swings from most competition growing up. It’s easier to get the bat under a pitch the higher it is. But in 2019 Newsome started throwing up, the ball that is. Up with the heater he’d refined at Gas Camp, and the results were eye-opening.
Without sacrificing his command, he blistered through the hitter-friendly Cal League. His numbers sustained in AA-Arkansas, but the peripherals did not, putting the breakout on hold. Newsome told Baseball America he wore down by late season, with the zip fading somewhat from his heater by late season, and his training this off-season focused on maintaining that endurance. His 5’11 frame is strong in the lower half, and Newsome evokes Dan Altavilla to a degree with his powerful, compact delivery. But where Altavilla finishes like he’s hurtling a javelin, Newsome seems to be throwing darts. The spin rate numbers on his fastball help it play up despite mere low-90s velo, and a slider/changeup combo keep him competitive in and below the zone’s lower half. The lack of projection on his frame, average velo, and weaker numbers upon facing heightened competition are what have him ranked low, but Newsome has gone from a guy staring down what could’ve been his final pro season to a guy one good season from making a big league debut. ~JT