Pitcher Spotlight: Can We Trust The New Jakob Junis?

After spending the majority of the season struggling to get his footing as a rookie, Jakob Junis has started to blossom as a starter for the Royals, holding a marvelous 1.80 ERA, near 9.00 K/9, and 0.36 BB/9 across his last four starts. His latest was an impressive eight strikeout performance in 5.2 frames against the Rays, sparking many owners to get on board. But should we be trusting Junis to be productive during the final month of the season?

To answer that question, we should take note of Junis’ most dramatic change: he’s turned himself into a two-pitch pitcher by throwing his Slider 46.7% of the time in his last two starts. Chris Archer, Tyson Rossand Rich Hill have had success with a similar approach, and let’s scrutinize Junis’ two pitches to determine if he can do the same.


We have to lead with his Slider since it’s the money pitch and made Junis a major leaguer. To get introduced, check out this 0-0 Slider to Steven Souza Jr. that was flat out nasty:

It shouldn’t be much of a surprise that batters are hitting just .197 with a .053 ISO across the 273 he’s thrown so far in the majors. Junis’ Slider is also inducing whiffs at a 18.0% rate and chases off the plate at a 43.1% clip despite tossing it in the zone at a high 47.3% mark. In other words, Junis can throw the pitch for a strike when he wants to but can also get batters fishing when he needs a putaway pitch. It’s really good.

Junis showcased all of its uses across this outing on Tuesday night. There was your standard get-me-over first pitch strike:

A 0-1 Slider to quickly get to two strikes:

A beautiful putaway slide piece to end shut the door on three pitches:

And your 1-1 offering to induce a quick out:

This last pitch has been labeled as a Curveball since it came in around 6mph slower than the other Sliders we’ve seen, but I’m not convinced. I was able to talk to Junis on Twitter about his new Slider, where he told me he was focusing on “throwing it softer and harder” to mix it up against batters and keep them off balanced. Sounds like an excellent way of getting more out of your #1 pitch instead of relying on weaker options in your arsenal.

There isn’t much more to say about Junis’ Slider that you wouldn’t already know just from watching these GIFs. It’s fantastic and a signature pitch that he has every reason to throw nearly 50% of the time as it can do whatever he wants it to. It instantly makes his other pitches better simply because hitters have to be always on alert, and let’s hope Junis keeps up its high usage rate moving forward.


With a great secondary pitch in his back pocket that Junis is having confidence throwing half the time, the focus shifts then to his Fastball. The aforementioned trio of Chris Archer, Tyson Rossand Rich Hill each have different areas where they can be effective with their heater. Archer’s Fastball touches the mid-to-upper 90s and can help mask mistakes with the pitch. Ross gets a ton of sink on his heater, inducing plenty of groundballs and avoiding the barrel of the bat. Hill’s delivery provides plenty of deception for his Fastball, while hitting his spots frequently. Looking at Junis’ Fastball, he definitely doesn’t get Archer’s heat as he dances between 90mph and 91.5mph with his Sinker and Four-Seamer. But how about his movement? Let’s take a look at it:

It’s…fine. In his past four starts he’s essentially introduced his Sinker to his arsenal and has featured it 20.6% of the time. It doesn’t have the wild movement that will freeze hitters or turn their bats into firewood constantly, which means he is going to have to rely on pinpointing its location if he’s going to have consistent success.

So how is the command of his Four-Seamer and Sinker? Here are some of the pitches I saw against the Rays:

This isn’t the fairest presentation of Junis. He obviously made plenty of good pitches with his Fastball during the course of this game and I’m showing you some of the worst. However, it’s important to note that just one of these were punished, leading to a single to right-field. These pitches are coming near the dead center of the plate at a cushy 90-91mph with average movement and they were mostly fouled off or poorly hit for an out. And the one that was driven was limited to just a single instead of extra-bases.

To be fair, this is what his Fastball looks like when he executes it well:

In the first GIF we have Junis hitting the glove and getting a well deserved out by jamming Lucas Duda inside. In the latter GIF Junis hits his spot twice in two different at-bats to Brad Millereach time getting a swing-and-a-miss.

Junis is far from being wild with his heater (this is nothing close to Lucas Giolito during his 2017 debut or a Francisco Liriano situation), but the main takeaway should be that Junis has a very small margin of error with his Fastball. It doesn’t have vicious movement or elite velocity that will allow him to get away with poorly commanded pitches. This forces Junis to be on point with his command in each start if he’s going to be successful and I’m not sold that he can be that type of finesse pitcher to maintain a stellar one-two punch.


It’s a tough bet to make. While Junis’ Slider is without a question going to be effective in each start, he can’t do it with his slide piece alone. His Fastball isn’t at a place where we can bank on him to continue getting outs with the pitch, as it doesn’t have the velocity Chris Archer features, the movement Tyson Ross gets, nor the deception and precision of Rich Hill. I don’t see a major impact arm down the stretch as seems destined to run into trouble with his Fastball, but if you’re in need of strikeout upside while being able to roll the dice on ratios, Junis can certainly help in a 12-team league.

We hoped you liked reading Pitcher Spotlight: Can We Trust The New Jakob Junis? by Nick Pollack!

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Nick Pollack is the founder of PitcherList.com and has written for Washington Post, Fantasy Pros, and CBS Sports. He can be found making an excessive amount of GIFs on twitter at @PitcherList.

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Mario Mendoza
Mario Mendoza

Excellent article. You’re a great talent addition for fangraphs.