Projecting the Prospects Seattle Traded Yesterday

The Mariners continued their early-January flurry of activity yesterday, swinging two trades in short succession. First, they dealt left-handed pitchers Thomas Burrows and Luiz Gohara to the Braves for Mallex Smith and intriguing arm Shae Simmons. They promptly flipped Smith, along with prospects Carlos Vargas and Ryan Yarbrough, to the Rays for Drew Smyly.

The most interesting players in this deal are likely the two who’ll make an immediate big-league impact — Smith and Smyly — the former of whom KATOH adored heading into 2016. But the other players changing hands also have their merits. Here’s what my KATOH system has to say about the players who spent most of 2016 playing in the domestic minor leagues.

Note that new Atlanta prospect Burrows is omitted due to a lack of professional experience; new Tampa prospect Vargas, because KATOH doesn’t account for Dominican Summer League numbers, which are the only sort Vargas has produced. KATOH denotes WAR forecast for first six years of player’s major-league career. KATOH+ uses similar a methodology with consideration also for Baseball America’s rankings.

*****

Luiz Gohara, LHP, Atlanta (Profile)

KATOH: 3.1 WAR
KATOH+: 2.7 WAR

Gohara posted an ERA well above 5.00 over his first three seasons as a pro, but really found his groove last year as a 19-year-old. In 15 starts across two levels of A-ball, he pitched to a dazzling 3.04 FIP on the strength of a 29% strikeout rate. Gohara was one of the more dominant arms in the low minors.

KATOH isn’t completely sold yet, though, as Gohara has a few negative variables in his profile. For one, he was decidedly bad as recently as 2015, which wasn’t terribly long ago. He’s also never pitched above Low-A, meaning he’s largely untested against high-quality hitters and still has a few years of development that have yet to occur. Even his strong 2016 numbers came in a small sample — 79 innings — so KATOH’s a bit skeptical of the track record he does have.

Gohara’s numbers are worth crunching, but he’s also a case where it probably makes sense to lean on the scouting reports more so than the stat line. KATOH is always hesitant to get behind low-minors pitchers, especially in small samples. Pitchers can get by with iffy stuff down there, and KATOH can’t always tell the difference between guys like that and real prospects. But, as Eric Longenhagen noted, Gohara’s stuff is very good. That data is more important in Gohara’s case.

To put some faces to Gohara’s statistical profile, let’s generate some statistical comps for the hard-throwing lefty. I calculated a weighted Mahalanobis distance between Gohara’s performance this year and every A-ball season since 1991 in which a pitcher recorded at least 350 batters faced. In the table below, you’ll find the 10 most similar seasons, ranked from most to least similar. The WAR totals refer to each player’s first six seasons in the major leagues. A lower “Mah Dist” reading indicates a closer comp.

Please note that the Mahalanobis analysis is separate from KATOH. KATOH relies on macro-level trends, rather than comps. The fates of a few statistically similar players shouldn’t be used to draw sweeping conclusions about a prospect’s future. For this reason, I recommend using a player’s KATOH forecast to assess his future potential. The comps give us some interesting names that sometimes feel spot-on, but they’re mostly just there for fun.

*****

Ryan Yarbrough, LHP, Tampa Bay (Profile)

KATOH: 1.1 WAR
KATOH+: 1.1 WAR

Yarbrough pitched exclusively at Double-A last year and did so effectively. The 6-foot-5 lefty spun a 2.95 ERA across 128 innings and 25 starts. Those are the encouraging numbers, while the rest of his profile isn’t as rosy. Although he’s had strong results, Yarborough’s achieved them without striking many batters out — a trait that doesn’t generally portend future success in the big leagues. He’s also 25, which is quite old for a Double-A pitcher. Yarbrough has succeeded in the high minors, which is commendable, but my math doubts he’ll be anything more than a replacement-level arm.

Here are Yarbrough’s comps: