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The Improbable Prospect List Rise of Robert Gsellman

You may have been surprised to see Robert Gsellman, erstwhile Jacob deGrom clone—seriously, have you seen how much the two look alike with deGrom’s new heel beard?—and contender for the Met fifth starter position, pop up in the top handful of pitching prospects in baseball in the recently released Baseball Prospectus 101. On the other hand, maybe you’re not surprised to see him that high, because you’re a diehard Mets fan that bought in already. We* ranked Gsellman No. 17 overall, behind only Alex Reyes (since felled by a torn UCL), Lucas Giolito, and Tyler Glasnow among the game’s pitching prospects.

(* – Editor’s Note: Jarrett was part of the team, led by BP Mets’ Jeffrey Paternostro, that contributed to the 2017 BP 101 rankings.)

It’s certainly true that Baseball Prospectus is, to this point, the only major outlet to rank Gsellman quite that high; John Sickels of SB Nation ranked Gsellman 59th and Keith Law of ranked Gsellman 76th. In our Mets Top 10, we graded Gsellman as an OFP (overall future potential) role 70 and likely role 60; this was the highest combined grade pairing we gave to any pitcher this year, and Gsellman ranked fourth of the five we graded that high.

In less-scouty terms, what do we think about Gsellman? Think of OFP as the roughly the 75th percentile outcome for a player, a reasonable high-side outcome, and the likely role as about the median outcome. A role-70 pitcher is a number two starter or elite reliever, and a role-60 pitcher is a number three starter or good closer. When putting this together with calling Gsellman a 70 OFP/likely 60, you should note something immediately: BP isn’t projecting Robert Gsellman’s career outcomes to look like Robert Gsellman in 2016. 2016 Gsellman pitched like a role 80 ace, and we’re expecting that to backslide a good bit, or else he’d be a likely 80 and the best pitching prospect since Stephen Strasburg nearly a decade ago. Gsellman might yet be an ace, but nearly every good or better pitching prospect has “ace upside” if everything goes right. Most of the time, something goes wrong. Put another way, there’s a list of the 10 top non-Gsellman pitching prospects later in this article, and it’s likely that around two of them will turn into true aces.

Good luck guessing which two it will be.

What does Robert Gsellman look like as a prospect now now? We have very reliable velocity data thanks to PITCHf/x and Brooks Baseball; he was consistently sitting from 93-96 with his fastball, often leaning on a two-seam with absolutely vicious sink and run. His groundball rate, as it has been throughout his minor-league career, was excellent. This is a pure 70-grade fastball in every sense, just a tick or two short of an 80. His most used secondary offering was the vaunted Warthen Slider, a pitch on the border of a slider and cutter that Gsellman has taken to like a fish-to-water, running it anywhere from the high-80s all the way up to 92. It’s not quite Noah Syndergaard’s slider, but it’s absolutely an out pitch and a plus secondary offering, at least a consistent 60-grade pitch and flashing a 70. Gsellman has always shown good feel for his curveball, and it’s at least a MLB average 50-grade pitch now with higher future potential. His change … well, he threw it five percent of the time in the majors. It’s below-average, but a pitch thrown four or five times a start is a “show-me pitch” and no more, and his two-seamer gives him a higher-priority pitch that moves armside.

What are the risks in Gsellman giving back more of his 2016 gains than we project? He’s only been throwing this hard for about a half-season, and sometimes guys can have velocity pop like this and not maintain it over the long haul. He’s had enough injury woes—though mostly minor and not to his pitching arm—that he’s never cracked 160 innings in a professional season, so the generic concerns about durability exist. You’ve also got that below-average change and some fastball command nitpicks, but if you read our system top 10 lists, you learned that there’s barely a young pitcher in baseball who couldn’t use a half-grade on the command or change.

Who are the pitchers we’ve ranked around Robert Gsellman and how do they stack up with Gsellman? Without giving away a dozen scouting reports, ahead of Gsellman are:

  • Alex Reyes: Well, he looked like the safest bet and is now undergoing Tommy John surgery.
  • Lucas Giolito: His 2016 included the velocity and command regression that worry us about Gsellman.
  • Tyler Glasnow: He’s possessed of frequent command problems, albeit with greater raw stuff that RG65.

Behind Gsellman, but still in the top 30, are:

  • Josh Hader: Owns an unorthodox motion that raises injury/reliever red flags.
  • Brent Honeywell: Owns an unorthodox everything.
  • Yadier Alvarez: Has thrown only 39.3 innings above short-season ball, and needs a third pitch.
  • Anderson Espinoza: Needs more than only one season in full-season ball, is slight of frame, and his command and secondary offerings have quite a long way to go.
  • Mitch Keller: Has a similar “pop-up” type profile to Gsellman, but did it in A-ball instead of the upper-minors and MLB.
  • Francis Martes: He’s actually a good comp for where Gsellman is now in stuff and overall profile, but is still in Double-A.
  • Jason Groome: Is great, but has a grand total of 6.7 professional innings.

The comparison that has tended to bubble up the most over the past six months is Gsellman to Giolito. They’re both tall California prep righties and–until the Adam Eaton trade–both were prominent National League East prospects. Everything up until they both reached the majors in mid-2016 would tell you that Lucas Giolito was a far, far better prospect than Robert Gsellman: rankings, old reports on stuff, draft position, developmental time, minor-league stats … literally everything. Then they got to the majors and Gsellman’s two-seamer was coming in harder than Giolito’s flat four-seamer, Gsellman was running two distinct breaking balls grading better than Giolito’s once-future 80-grade curve, and Gsellman looked miles ahead on command and overall polish. Things changed very quickly, as tends to happen with pitching prospects.

Yet, everything that happened before this summer still matters. We do still have Giolito seven spots ahead of Gsellman, after all. We didn’t quite give Gsellman that Strasburgian projection of repeating 2016 over a full season over and over again for the next decade. But you can make the argument that Robert Gsellman compares favorably to nearly every pitching prospect in baseball. And if you can do that, you’ve got yourself a top prospect in his own right.

Photo Credit: Bill Streicher-USA TODAY Sports

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2 comments on “The Improbable Prospect List Rise of Robert Gsellman”

Ryan Silva

We might as well start researching the “Warthen Sinker” at this stage too, because Syndergaard and Gsellman especially will just run that thing in at just about any count for impossibly great results.

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