2017 Breakout Prospect: Is The Diamondbacks’ Jon Duplantier For Real?

by Eric Stashin (aka The Rotoprofessor)

When the Diamondbacks selected Jon Duplantier in the third round of the 2016 draft it would’ve been hard to envision him developing as he has.  Splitting time between Single-A and High-A the 23-year old righty was dominant as the accolades are already starting to be bestowed upon him.  The newly dubbed MLB Pipeline Pitcher of the Year shined at both levels that he played:

  • Single-A – 72.2 IP, 1.24 ERA, 0.83 WHIP, 9.66 K/9, 1.86 BB/9, 50.0% GB%
  • High-A – 63.1 IP, 1.56 ERA, 1.15 WHIP, 12.36 K/9, 3.84 BB/9, 51.9% GB%

Those are eye-popping marks, but we also can’t get cloudy eyes and ignore the potential negatives.  Let’s take a look at both the good and the bad:


The Stuff (as per MLB.com):
Duplantier is athletic and physical, with the repertoire to succeed in a rotation. He can throw his sinking fastball in the 91-96 mph range with excellent extension, making it appear to get on hitters more quickly. He has a power curve that flashes plus when he stays on top of it. When he doesn’t, it gets slurvy. He also shows a good feel for a changeup.


The Good:

  • According to MILB.com his 1.39 ERA “was the second-best mark in MiLB in the last 25 years, behind only Justin Verlander’s 1.29 ERA posted in the 2005 season. Duplantier was also third in MiLB with a .192 batting average against and 12th with a 0.98 WHIP.”
  • His 14.0% SwStr% between the two levels shows that the strikeout stuff is there (and the improvement upon his promotion just adds to the appeal)
  • The groundball rate is above average and the fact that he avoided home run issues pitching in the Cal League (0.28 HR/9) is highly encouraging
  • Has the size we look for (listed at 6’4” and 225 lbs.)


The Bad:

  • You can argue he was old for the levels in which he pitched
  • The jump in his walk rate, more than doubling, is something that we’ll have to continue to monitor
  • There was a bit of luck in the ERA, as his strand rates were 87.3% and 85.9%
  • He’s already had some shoulder trouble, missing the entire 2015 season in college
  • The poor track record of pitcher’s selected out of Rice University


The Conclusion:
The good obviously far outweighs the negatives and he deserves all of the accolades that he’s going to get this offseason.  That said there are some warning signs that we can’t ignore and we do want to proceed with cautious optimism.  There’s no questioning the upside, but he’s likely not quite this good and could take a significant step backwards if the control does not turn back around.

Current Grade – B+

Sources – MLB.com, MILB.com, Fangraphs

Leave a Reply

Your email address will not be published. Required fields are marked *