The Kansas City Royals seem set roster-wise for Spring Training, and a key for the Royals in 2023 will be how their pitching develops under new manager Matt Quatraro, pitching coach Brian Sweeney, and the Royals coaching staff.

It’s been a frequent point of discussion this week, as MLB.com Royals beat writer Anne Rogers made pitching development the focus of her weekly newsletter, and David Lesky of Inside the Crown posted a thorough article about what to expect from the staff and pitching staff for the upcoming season.

The #Royals believe the big league instruction was the problem for the young pitchers. They also believe they fixed that. The time is now for the young guys to prove they belong. I'm very curious to see how the new coaches help. https://t.co/Sh8HMquJhC

— David Lesky (@DBLesky) February 7, 2023

I am not going to dive too much into the staff as a whole, as Rogers and Lesky have already done a great job of doing that in their recent articles. That being said, there is one pitcher that I think is a bit of a wildcard on the Royals’ 40-man roster that could be utilized in a variety of spots:

And that pitcher is Jon Heasley, who is looking to bounce back after a rough first full season in the Majors last season.

---

Heasley’s Struggles With Command in 2022

The Royals’ vaunted 2018 draft class consisted of many college pitchers, including Heasley, who was drafted in the 13th round out of Oklahoma State.

After struggling in 2018 in the short-season Pioneer League with Idaho Falls (5.15 ERA in 50.2 IP), Heasley has progressed and developed quickly in the Royals’ Minor League system since. He posted a 3.12 ERA in 25 appearances (20 starts) and 112.2 IP in Low-A Lexington in 2019 and followed that up with an impressive 3.33 ERA in 22 appearances (21 starts) and 105.1 IP in Double-A Northwest Arkansas in 2021.

The strong campaign with the Naturals earned Heasley a call-up to the Majors late in the season. His three-start, 14.2 IP debut wasn’t eye-popping, as evidenced by his 4.91 ERA. However, he did show some flashes of promise, especially in his debut outing.

Jon Heasley goes to the elevated fastball for his first MLB strikeout. pic.twitter.com/pp0Q09iaQv

— MLB Pipeline (@MLBPipeline) September 18, 2021

Last season, it appeared as if the last spot in the rotation was up for grabs between Heasley, Brady Singer, and Daniel Lynch. Lynch nabbed a guaranteed spot in the rotation, and Singer initially was regulated to the bullpen with Heasley starting the year in Triple-A Omaha. Heasley did get called up to the Majors on May 12th due to the Royals’ pitching staff’s struggles early in the year, and he spent the majority of the season in Kansas City, making 21 starts and pitching 104 innings.

Unfortunately, the results were not great for Heasley, as he not only posted a 5.28 ERA, but also a 5.67 FIP. Additionally, Heasley ranked last of all Royals starting pitchers with 10 or more IP in fWAR (-0.5).

A big issue for Heasley so far in the big leagues has been his decline in command, which can be seen in the difference in his Major League and Minor League K/BB ratios. Notice how solid his K and BB numbers look in the minors, and how greatly they contrast with what he produced in the Majors in 2021 and 2022.

Even though he didn’t strike a lot of guys out in 2021, he at least kept the walks manageable, as evidenced by his 2.00 K/BB ratio. Unfortunately, things went south with the Royals in 2022, as his BB/9 inflated from 1.84 in 2021 to 4.07 in 2022. That BB/9 was not only a career-high for him as a professional pitcher, but his K/BB ratio was a career-low as well.

For a pitcher who has struggled with the longball (career 1.67 HR/9 allowed in the Majors), those kinds of issues with locating the ball certainly don’t bode well for his projection in the long-term, and this struggle is a big reason why Roster Resource thinks he’s on the outside-looking-in when it comes to making the Opening Day roster this year.

Now it’s interesting to note that Heasley did stabilize his walk rate after a rough start to the year, which can be seen in his BB% rolling chart from the 2022 season, via Baseball Savant.

The BB% tended to be above the league average more often than not. Then again, he did keep it in the six to nine percent range for a little bit (from the 150 plate appearance mark to the 300 mark), so Heasley certainly has the potential to be at least league-average when it comes to allowing walks. If he can do that in 2023, that could give him a shot to at least earn some kind of spot on the active roster, whether it’s in the rotation or bullpen.

For a team that ranked 29th last season in BB/9 as a staff, according to Fangraphs, the Royals need pitchers who can throw strikes and limit free passes on the basepaths.

On the other hand, though, Heasley will have to increase the strikeouts if he wants to be more effective with the Royals in 2023. While his BB% slightly increased above league average around the halfway point of his season in 2022, his K% went in the wrong direction correspondingly (i.e. down), which can be seen in the chart below:

The increase in BB% and decrease in K% over the course of the season could hint at fatigue, which would make sense for Heasley in his first full MLB season (which was the case for many Royals young pitchers as well).

Nonetheless, it will be interesting to see what Heasley did this offseason and does this Spring to hopefully avoid that “command wall” he hit in 2022.

---

Can Heasley Find the Right Pitch Mix?

A big issue for Heasley is that it’s hard to determine what his go-to pitches going forward are. A look at his run value and pitch arsenal metrics via Savant paint a difficult picture for Royals fans when it comes to determining what Heasley’s best pitches were a season ago.

Obviously, nearly all of Heasley’s pitches produced high run value, which is not good (one wants it to be negative). Looking beyond his run value number isn’t necessarily more encouraging either.

His four-seamer was actually a decent pitch on an expected batting average end (xBA) with a .258 mark, but it only produced a whiff rate of 13.9 percent and put away rate of 14.1 percent.

As for his curveball, the breaking pitch produced the highest whiff rate (25.6) and second-best put-away rate (15.6 percent), but he allowed a 57.7 percent hard-hit rate on the pitch, which was the second-highest rate of the five pitches he threw a season ago.

Let’s take a look at the difference in the heatmaps of curveballs Heasley threw that generated whiffs and ones that gave up base hits, via Savant (scroll right for hits; scroll left for whiffs).

Here’s an example of Heasley hanging the curve too much in the zone against Chicago’s Lenyn Sosa, who blasts it over the left field wall and into the fountains at Kauffman Stadium on August 9th.

It will be interesting to see if Sweeney and the Royals coaching staff will want him to continue to develop the curveball or want him to utilize the slider more. He utilized the slider more heavily against right-handed batters last season, as he threw it 20.8 percent of the time against right-handed hitters in comparison to only 5.2 percent against lefties, according to Savant.

Comparatively, his curveball generated a 28.7 CSW% (called strike plus whiff rate) while his slider only generated a 21.8 CSW%, according to Pitcher List data. So it may still be worthwhile for Heasley to still employ the slider on a semi-regular basis.

His CSW% was 24 percent against right-handers though, and it does offer some sharp late drop, which proved more effective against right-handers when located well, like this one against Cleveland’s Austin Hedges.

The changeup seems to be an established part of Heasley’s repertoire (21.3 percent usage rate) and he had some success with it in terms of generating soft contact (33.8 percent hard-hit rate). It will be interesting to see though if he will continue to have that changeup work off his four-seamer, or if Heasley will utilize his sinker more to give himself more variety against opposing hitters.

Notice in the chart below how Heasley’s sinker usage went slightly up (along with his changeup usage) in September and his four-seam fastball usage went down.

Will we see the Royals staff have Heasley advocate for the slider more, which posted solid whiff rate numbers (24 percent), but horrendous hard-hit (77.8 percent) and expected wOBA (.469) numbers?

Or will Heasley continue to refine the four-seamer as his primary pitch in 2023?

The four-seamer ranked in the 70th percentile in fastball spin, which is pretty positive. It also sports good vertical movement, especially when compared to his other pitches, as evidenced in his pitch break percentage vs. average chart below, via Savant.

Here’s an example back in June of Heasley’s four-seamer not just showing nasty movement, but being located well in the lower part of the zone against San Francisco’s Mike Yastrzemski. The pitch freezes him up for the backward K.

#️⃣4️⃣ on #TheFilthiest for 2022-6-15: Jonathan Heasley's 4-Seam Fastball to Mike Yastrzemski 😯

MPH 🚀: 94.0
RPM 💫: 2331
FiFaX 🤯: 0.730@Royals #TogetherRoyal | @SFGiants #SFGameUp pic.twitter.com/OCgt6HiCRj

— Dayv Doberne ⚾ (@Sunyveil_Sports) June 17, 2022

The Royals pitching coaching team has strongly been focused on pitch shape and movement this offseason, which appears to be a specialty of assistant pitching coach Zach Bove.

One has to wonder if those conversations with Bove can help make Heasley’s four-seamer even more effective. If they do, that could also result in him maybe condensing his pitch mix a bit, starting with eliminating the sinker, which he only throws 3.3 percent of the time anyways.

Then again, cutting the pitch mix could mean a bullpen stint may be more likely for Heasley in 2023 and beyond.

---

Could Heasley Find a Unique Role Out of the Bullpen?

The one thing that should be expected from new manager Quatraro is that he will utilize the pitching staff differently in comparison to his predecessor Mike Matheny.

Quatraro seems to value and emphasize depth as the key to building a successful MLB team, and the more young arms the better, even if they take their lumps in the process.

"Every good team has pitching. There is a lot of talent… They have taken their lumps in the big leagues."@Royals manager Matt Quatraro is excited for the development of a young rotation in Kansas City.#MLBTonight | @AlLeiter22 | #TogetherRoyal pic.twitter.com/czG2SWMAkL

— MLB Network (@MLBNetwork) December 6, 2022

As of now, the Royals will be looking at a pitching rotation that consists of at least Zack Greinke, Jordan Lyles, and Brady Singer. After those three though, the rotation looks a lot more up in the air.

It appears likely that Daniel Lynch will acquire one of those two remaining spots, barring a disastrous Spring Training. The same could also be said of Brad Keller, who is in his last year of team control and is slated to earn $5.5 million this year. Keller has certainly shown flashes before but hasn’t put it together over a full season, especially over the past two seasons.

That leaves Ryan Yarbrough, Carlos Hernandez, Angel Zerpa, Max Castillo, Kris Bubic, and Heasley as options who could compete for one of those two spots, though they seem more like long shots compared to Lynch and Keller.

Then again, they could be utilized creatively out of the bullpen by Quatraro, perhaps in an opener or long relief role (pitching off the opener), which was pretty commonplace in Tampa Bay under manager Kevin Cash (for whom Q was a bench coach for).

That kind of role would make sense for Heasley, especially considering his struggles last year after going through the first time of the order, according to Fangraphs.

When taking a look at the projected bullpen via Roster Resource, it appears that Hernandez is being tabbed for the long relief role. That said, he may be better in a more traditional bullpen role in the middle innings, especially with a four-seamer that can sit in the upper 90s and touch 100 MPH with regularity.

Thus, with so many lefties already in the bullpen, it could make sense for Heasley to swap with Josh Taylor, especially since Taylor may need more time to acclimate after missing nearly all of 2022 due to recovery from Tommy John.

Heasley in that “swing” spot could be a perfect fit for both the Royals and Heasley himself.

Then again, one could also imagine Bubic, Castillo, or Zerpa in that role, though I imagine the Royals will want Castillo and Zerpa to headline the Omaha rotation and see them develop their pitches a bit more in the Minor Leagues for now.

Which just leaves Bubic and Heasley as the serious contenders for that role…

And that “swingman” battle should make Royals Spring Training even more intriguing to follow for Royals fans in anticipation of Opening Day on March 30th.

Photo Credit: Tim Heitman/Getty Images