Buy ‘Em or Deny ‘Em: Which Streaking Starter Is Worth Adding (Wood, Karns & More)

by Eric Stashin (aka The Rotoprofessor)

Figuring out if a hot pitcher is for real or not isn’t always an easy task.  Sometimes pitchers can look like all world performers for a few starts, only to see the bottom fall out in short order.  Who of the hot pitchers are for real?  Who should we be ignoring (or selling)?  Let’s take a look:

Alex Wood – Los Angeles Dodgers
It certainly appears like Wood has turned back the clock, as he is checking all the boxes in regards to what we look for from a pitcher:

• Strikeouts – 12.11 K/9
• Walks – 2.78 BB/9
• Groundballs – 62.8%

He’s always primarily been a sinker ball pitcher, and that hasn’t changed this season (50.00%).  The adjustment he has made is throwing his changeup more, and his current 28.1% would be a career high.  That, along with his curveball, have been swing and miss pitches (Whiff% of 16.03% and 16.49%, respectively).

Amazingly there is nothing lucky in the numbers, considering a .282 BABIP and 72.3% strand rate.  You can argue that his line drive rate will rise (15.1%), but even that isn’t enough.  Increasing his changeup usage has obviously helped keep opposing hitters off balance (11.9% SwStr%, 33.1% O-Swing%), and he’s always shown good control and an ability to generate groundballs.

Verdict – Buy ‘Em

Nate Karns – Kansas City Royals
He’s not throwing any harder (93.0 mph vs. 92.9 in ’17) and there hasn’t been a major shift in philosophy.  He is throwing his changeup a little bit more (10.71% to 6.90%) and his curveball less (36.51% to 32.58%), but is that enough?  He’s been a strikeout machine of late (22 K over his past two starts), and his overall metrics make him look like an ace:

• 55.2% groundball rate
• 12.9% SwStr%

Is it possible that his curveball, which carries a 24.60% Whiff%, has become that much more dangerous of a weapon?  Opponents are hitting .159 with a .270 SLG against it (and .160 against his changeup).  It’s the development of those pitches that are and will ultimately dictate his future success.

Is he worth a short-term add?  Absolutely, and you should ride him while he’s hot, but don’t become infatuated.  It’s hard to imagine him pitching like he has of late.

Verdict – Buy ‘Em (short-term, but long-term Deny ‘Em)

Luis Perdomo – San Diego Padres
Over his first five starts of the season Perdomo is showing the full skill set that we look for:

• Strikeouts – 7.94 K/9
• Control – 3.18 BB/9
• Groundballs – 69.5%

Obviously neither the strikeouts nor the walks are elite numbers, but that type of groundball rate in Petco Park makes for significant upside potential.  The number makes sense, as he’s utilized his sinker 58.76% of the time, so even if there is a regression in the mark it should continue to keep him relevant.

He’s complementing it with a curveball that’s generating significant swings and misses (24.02%), but you have to wonder if there’s enough variety in his repertoire.  He throws his splitter 9.02% of the time, so it’s a complimentary pitch to keep people honest but he primarily uses just two pitches.  With that in mind, his regression as the game progresses makes sense:

• First 9 Batters – 2.53 ERA
• Second 9 Batters – 0.00 ERA
• Third 9 Batters – 14.21 ERA

As teams see him more there’s an increased risk of poor production, so while it’s been an impressive start he’s going to be a tough investment moving forward.

Verdict – Deny ‘Em

Sources – Fangraphs, Brooks Baseball CBS Sports

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