The New York Yankees made their first big move of the offseason by sending three prospects to the Seattle Mariners for gigantic Canadian left-hander James Paxton. The Yankees add a power arm after their rotation took a beating in an ALDS loss to Boston, while Seattle continues a retooling effort that began in earnest when the Mariners traded starting catcher Mike Zunino to Tampa Bay two weeks ago. But while Zunino and outfielder Guillermo Heredia were traded for Mallex Smith, a 25-year-old three-year MLB veteran, the return for Paxton is three minor leaguers, headlined by 22-year-old left-hander Justus Sheffield. By trading their best pitcher for prospects, the Mariners seem to be signaling that this retooling effort is now a full-blown rebuilding project.
Paxton is perhaps baseball’s best example of a high-risk, high-reward pitcher. When he’s on, he’s as good as any pitcher in baseball—last year, his average fastball velocity, 96.1 mph, was the second highest among left-handed starters with at least 100 innings pitched, trailing only AL Cy Young winner Blake Snell. In May, Paxton struck out 16 Athletics on just 105 pitches over seven innings, then followed that effort up with a 99-pitch no-hitter in his next start. In 2018, his strikeout rate, 32.3 percent, was fifth highest in baseball.
The risk, however, is that from a durability standpoint Paxton makes Lance McCullers look like Livan Hernandez. His 28 starts and 160 1/3 innings pitched in 2018 were both career highs—he’s never qualified for an ERA title and managed to throw 100 innings in only three of his six big league seasons. And while Paxton’s recent emergence sometimes makes it seem like he’s younger than he is, Big Maple, as he’s called, turned 30 two weeks ago and is two seasons from free agency. If the Yankees can somehow turn him into a consistent 30-start-a-year pitcher, they’ll look like geniuses for trading only one top-50 prospect, Sheffield, for a genuine ace. But it’s just as likely that Paxton can’t stay off the DL and goes down as the Canadian Carl Pavano. Perhaps in recognition of this fact, the Yankees still intend to pursue free agent starters J.A. Happ and Patrick Corbin, reports Jon Morosi of MLB Network.
This trade’s all the more perilous for the Yankees because Sheffield is major league ready and can therefore offer an immediate performance comparison should Paxton falter. Sheffield was a 2014 first-round pick by the Cleveland Indians and one of the major pieces in the Andrew Miller trade two years ago. He made his big league debut this past September and has a mid-90s fastball with a plus slider and a change-up to fend off opposite-handed batters. If Sheffield had stayed in the Yankees system, he might have broken camp in the big league rotation.
The Mariners are in a tough spot. Their core is aging—Paxton and the 27-year-old Zunino were two of the younger significant contributors on the club—and the club had 89 wins in 2018, which was its most since 2003 but eight short of the wild card. At the same time, their farm system is dogshit, which is an improvement on the state of the farm two or three years ago, when it was beyond dogshit. The moment he puts on a Mariners jersey and starts growing facial hair, Sheffield will become Seattle’s best prospect by far, and he might end the season as their best starting pitcher. With that said, Sheffield is far from a sure thing himself—all pitching prospects are risky to some extent, and sometimes short power pitchers with spotty command turn into Pedro Martínez, but sometimes they turn into Carson Fulmer, with all manner of variations in between. And even if he does turn out to be better than Paxton, Sheffield himself can’t right the proverbial ship all on his own.
The other two pieces in this trade are 25-year-old right-hander Erik Swanson and 23-year-old outfielder Dom Thompson-Williams, who played together for a year at Iowa Western Community College. The Rangers drafted Swanson in the eighth round in 2014 then traded him, along with two other prospects, to the Yankees for Carlos Beltrán in 2016. Swanson has a strong track record in the high minors—last year he posted a 2.66 ERA with a 10.3 K/9 ratio across three minor league levels, mostly out of the rotation, and given how frequently the Mariners go through fifth starters, we’ll probably see Swanson in the majors in 2019. But he’s also a 25-year-old who hasn’t made the big leagues yet, which indicates a relatively low ceiling.
The same is probably true of Thompson-Williams, who transferred to South Carolina for the 2016 season and, after a strong performance there, was drafted by the Yankees in the fifth round. Thompson-Williams can run a little and play center in a pinch, and in 2018 he developed some power for the first time, hitting 22 home runs and slugging .546 in high-A, though he was old for the level, so those numbers should be taken with a grain of salt. The realistic best-case scenario for Thompson-Williams is as a fourth outfielder—if you’re a Mariners fan and you liked Heredia, or Ben Gamel, or Nori Aoki, you’re going to love DTW.
This trade is easy to spin for both teams: The Yankees gave up just one notable prospect from a deep farm system for a pitcher with ace upside, while the Mariners got back a new organizational top prospect for a 30-year-old pitcher who’s never stayed healthy. At least for now—once Paxton and Sheffield take the mound next spring, we’ll learn whether one or both teams struck a tremendous bargain or made a gigantic mistake.