LL’s Top 50 Mariners Prospects 2019: #3 - Justus Sheffield

We’re almost there gang. This time tomorrow, you’ll (probably) have seen the official lineup for the Mariners’ first game of Cactus League play, and be able to listen to the sweat sounds of Aaron Goldsmith and Rick Rizzs coming through the airwaves as they broadcast real live Mariners baseball. That said, it’s important to remember that the minor leaguers figure to factor largely into the goals set out for the organization as a whole this year, and as such, we’ve taken the liberty to (further) familiarize you with LL’s Top 50 Mariners Prospects of 2019. These range anywhere from guys you’ll see in game action literally tomorrow to guys you may not see for 2-3 years if everything goes right.

That said, you may or may not be surprised to see that we here at the site have the system’s top prospects ranked in an order that may differ from many of the national outlets one would typically visit for their top organization prospect lists, and one of the bigger discrepancies you’ll find is right here.

It’s been five years since the Mariners last had a left-handed pitcher crack MLB.com’s Prospect Pipeline Top 100 prospects. The last man to do it, Danny Hultzen, has already gone through a full “flamed out prospect/comeback attempt” career arc in the time it’s taken for the organization to produce another southpaw to boast such honors. As the Mariners shopped homegrown ace James Paxton over the offseason, the Yankees constantly swirled as a likely landing spot for the ace from the Great White North, and just about any conversation involving the two sides started with the #31 prospect in baseball, Justus Sheffield.

The centerpiece of the deal that saw the Mariners jettison one of the most productive pitchers in franchise history, Sheffield was brought into the organization in hopes of developing into a foundational piece of the rotation on the next competitive Mariners team, and his track record through the minor league has provided every reason to think he’ll be able to do just that.

Still just 22 years old, the Cleveland Indians draftee already has five professional seasons under his belt and has produced a 3.08 ERA, 1.29 WHIP, 9.4 K/9, and 3.4 BB/9 through 487.2 career minor league innings, although his peripherals have suggested his ERA should hover closer to 4.00 than 3.00 due to the occasional lapse in control. The aforementioned tendency to lose the strike zone was on display during his three-game stint with the Yankees last summer when he was utilized for bullpen duty down the stretch. Despite holding the opposition scoreless in his first two outings, he worked himself into a jam in his debut, walking one and allowing two hits. Sheffield was all out of sorts in his final outing, surrendering three earned runs on two hits, a home run, and two walks.

Toeing the rubber at 6’0” 200lb, Sheffield defies the archetype of the prototypical ace pitcher, but his arsenal tells a different story. Despite looking a little more Jason Vargas than Max Scherzer, the Tennessee native has got stuff that can hang with the best of them, utilizing a three-pitch mix that contains a heater that ranges anywhere from 92-97mph and features both sink and run, as well as a hard slider he’ll use to bury hitters and an above-average change-up. His sinking fastball has factored into his development as a pitcher with ground ball-generating tendencies, and he’s actually produced really similar batted ball data throughout his minor league career as Marco Gonzales has during his time with the M’s. And the similarities don’t stop there either.

Gonzales is nearly the exact same size as Sheffield, and he too is a former top left-handed pitching prospect that Jerry dealt valuable assets to obtain in hopes of, well, basically doing exactly what they did with him. After looking like he may not live up to the hype that one time surrounded him, the Mariners’ coaching staff was able to turn Marco into one of the most valuable pitchers in the American League and still maintain control of for the remainder of his prime. If Sheffield reaches his theoretical ceiling, his pure stuff and preferential age compared to Gonzales could well lead to him developing into the better pitcher of the two.