Who is new Mariners LHP Justus Sheffield?

In the biggest trade yet of the Mariners’ offseason, Seattle on Monday agreed to send starting pitcher James Paxton to the New York Yankees in exchange for pitchers Justus Sheffield and Erik Swanson and outfielder Dom Thompson-Williams.

Mariners trade James Paxton to New York Yankees

The biggest name on that list is Sheffield, a left-handed pitcher who entered 2018 as the Yankees’ No. 1 prospect. Here’s what you need to know about the newest Seattle Mariner:

Full name: Justus Kane Sheffield
Position: LHP
Age: 22

It runs in the family

A native of Tullahoma, Tenn., Sheffield bypassed an opportunity to play college baseball in Nashville at Vanderbilt University. Instead, the 2014 Gatorade Player of the Year signed with the Cleveland Indians after being drafted 31st overall in that year’s dradt. Sheffield isn’t the first in his family to go pro – his brother is Dodgers right-handed pitcher Jordan Sheffield.

He could be the earliest contributor from Monday’s trade

Sheffield could be the first of the newest Mariners to contribute to next year’s roster.

“To be fair, he’s the one with any major league experience at all,” Mariners general manager Jerry Dipoto told 710 ESPN Seattle’s Danny, Dave and Moore shortly after the trade. “Which is to say he’s spent just less than two weeks in the big leagues in September last year. But Justus is (22) years old, real pedigree, former first-round draft, among the top 25 prospects in the game by most third-party measurements. But in this case, Justus comes into spring training… with a chance to make our club. … We would anticipate (Sheffield and Swanson) pitching here in Seattle before the summer is through.”

The Mariners made the trade with an eye toward the future

Dipoto told Danny, Dave and Moore that Seattle made the trade with an eye toward being as competitive as possible in the 2020-2021 season.

“Along the lines of what we laid out as a potential direction for us this offseason was to re-situate our roster and look toward 2020, 2021 as a time where we could take a step back this year to put ourselves in position to be as competitive as we can be at that point,” Dipoto said. “We’re trapped in the middle, so to speak, with a really talented American League around us. We’ve been pretty candid about our position there. And the ability to add young, upside talent, which started in last week’s deal with Tampa and really goes to a new level with this deal.

“Justus Sheffield is one of the more exciting young prospects in baseball, particularly among pitchers. (He has a) mid, upper-90s fastball, super athletic guy with an above- to well-above-average slider and a developing change.”

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