Back in July, it seemed like reliever Carlos Hernandez and his outlook was a difficult dilemma for JJ Picollo and the Royals front office.

At the end of July, Hernandez was posting a 3.57 ERA, 0.98 WHIP, and looking like the heir-apparent for the Royals’ closer position once Scott Barlow was traded away (he ended up going to San Diego right at the Trade Deadline). Hernandez was particularly dominant in July, as he not only posted a 1.35 ERA in 12 appearances, but he also posted a 0.75 WHIP and struck out 15 batters while only walking four in July as well.

Unfortunately, it’s been a much different story in August and September for the 26-year-old Venezuelan right-hander, which can be seen in his monthly splits below, via Savant.

In 11 appearances in August, Hernandez posted an 8.68 ERA and 1.93 WHIP in 11 appearances and 9.1 IP. That included 10 strikeouts and seven walks (as well as 11 hits allowed). September has been even worse for Hernandez. He not only has seen his ERA (16.62) and WHIP (3.69) nearly double from the previous month, but he also has matched his walk total from August already in five fewer outings and innings of work.

And thus, there are two questions in the minds of Royals fans regarding Hernandez:

What has been wrong with him over the past two months? What will Hernandez’s role be with the Royals not just in 2024, but long-term as well?

Let’s take a look at Hernandez’s profile and output over the past two months and determine if there could be long-term issues with Hernandez or if he’s simply suffering from a bit of fatigue after a long season.

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More Hard-Hit Balls and Walks Recently

When it comes to Hernandez’s biggest issues in August and September, his struggles can particularly be pinpointed to two primary areas: hard hits allowed and walks.

Below is a look at Hernandez’s hard-hit percentage breakdown chart throughout the season, via Savant, and notice in the image comparison how it correlates with the spike in wOBA allowed around the same period.

Around the 200th plate appearance and 140th batted ball this season, Hernandez has seen major spikes upward, which is not the direction any pitcher wants to see. In addition, he has also seen major spikes in his HR/FB rates over the past two months, according to Fangraphs batted-ball monthly splits.

Hernandez was plagued by a 20% HR/FB rate during the first month of play this year (as well as a 29.7% line drive rate). However, he showed improvement by neutralizing the home runs from May through July (2.57% HR/FB rate over those three months). That HR deflation, along with some improved swing-and-miss generation, was a big reason why he posted FIP marks of 0.91, 2.32, and 2.89 in May, June, and July, respectively, according to Fangraphs.

Over the past two months though, opposing hitters have been able to hone in on his stuff and in a big way.

His HR/FB rates have jumped up to 40% and 14.3% in August and September, respectively. Those massive spikes explain why his FIP has been a ridiculous 9.26 and 10.19 in August and September, respectively.

In addition to his struggles with giving up hard hits and the long ball, he also has struggled with walks over the past two months. Below is a look at his BB% breakdown chart this season, and much like his hard-hit and xwOBA charts, Hernandez sees a similar spike in BB% around the same time frame.

Furthermore, it wasn’t just Hernandez’s BB% that trended in the wrong direction over the past two months. He also saw a decrease in his K%, which in turn had negative effects on his overall K-BB% numbers over the past two months, according to Fangraphs.

In August, the K% seemed to be okay at 22.2%, it was just his high walk rate that deflated his K-BB% to 6.7% (a nearly 16-point drop from the previous month).

In September though, not only did his walk rate spike up to 25%, but his K% also dipped to 7.1%, a 15.1-point regression from August. As a result, his -17.9% K-BB% in September has been the worst monthly mark this season for Hernandez, though to be fair, it’s been a small sample at 4.1 IP.

Nonetheless, to see Hernandez struggle in these two areas has been disappointing, especially since he has worked in these areas throughout his career, especially in 2022.

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Is Pitch Quality An Issue for Hernandez?

A significant positive difference for Hernandez this year from 2022 has been his increase in four-seam velocity, which has made his four-seamer a more effective pitch this season.

Last season, Hernandez’s four-seamer averaged 96.8 MPH and only generated a CSW% of 23.5%, according to Pitcher List. This year? His four-seamer averages 99.1 MPH and has a CSW% of 27.6%, a 4.1% increase from a season ago.

In the clip compilation below, notice how much more velocity and movement his four-seamer has this season compared to 2022 (even if it produces the same result).

As a result of that increase, Hernandez’s four-seamer has been his most effective pitch on a PLV end this season, which can be seen in the PLV chart below.

In terms of overall PLV, Hernandez is posting a 5.12 mark this year. That PLV translates to a PLA of 3.85, which is pretty solid (a PLV of five is considered average). While his slider has been a slightly above-average pitch on a PLV end, his four-seamer has been his best pitch PLV-wise at 5.27.

That shows that despite Hernandez’s struggles, the quality of his fastball has still been there the past couple of months. Furthermore, the four-seam velocity has seemed to stay stable as well amidst these rough couple of months.

So if the pitch quality and velocity on his primary pitch have remained stable, what’s been the issue?

I think we can infer from Hernandez’s numbers that his command hasn’t quite been as pristine with his four-seamer over the past two months in comparison to the previous three.

Below is a chart that demonstrates the results of his four-seamer from March to July and a similar chart from August to September.

From March through July, Royals fans see a lot more strikeouts and fewer extra-base hits. From August to September though the strikeouts are far fewer (especially in that area above the strike zone) and the home runs are far more plentiful and obvious, unfortunately.

The reality is that Hernandez is simply catching too much of the plate with the four-seamer.

Even with premium velocity and better movement, opposing hitters have been able to do damage against it, especially when they are hunting for it early on.

That was the case against Cleveland on September 19th when Bo Naylor blasted a 99 MPH four-seamer from Hernandez into the Pepsi Porch.

Granted, the pitch quality of Hernandez’s secondaries, especially his splitter and curve, could use some work this offseason. On a PLV end, his curve was actually a decent pitch last season (which can be seen in his 2022 PLV chart). Hence, to see its regression in 2023 is a bit disappointing.

Improving the pitch quality on the breaking offerings (curveball especially) should be a priority for Hernandez this offseason. While the pitch quality remains solid on the four-seamer, Hernandez will struggle to have any long-term viability out of the bullpen until he can make his breaking offerings more dependable on a pitch quality end.

If assistant pitching coach Zach Bove and pitching coach Brian Sweeney can help him make strides in developing his secondaries this offseason, then it’s possible that Hernandez could take another positive step forward in 2024.

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What Should Hernandez’s Role Be Next Year?

When Barlow was traded at the Trade Deadline, it was expected that Hernandez would naturally move into the Royals’ closer role for the remainder of the year.

Unfortunately, Hernandez has proven that he cannot handle the pressure of the role both in the short and long term.

On a win-probability-added end, no Royals pitcher has been worse than Hernandez and his -1.98 WPA over the past two months. Furthermore, Hernandez’s seven meltdowns also led all Royals relievers over the past two months, according to Fangraphs. (Tucker Davidson has the second-most meltdowns at four.)

Additionally, Hernandez’s individual leverage splits data also doesn’t look too promising. In pressure situations, he has seen a sharp decline in strikeout rate as well as increases in walk and HR/FB rates, which can be seen in the table below.

The fact of the matter is that Hernandez probably isn’t a closer for this Royals team, whether it’s in 2024 or beyond.

That said, while he doesn’t have “closer material”, he still holds some value to this Royals bullpen in the long term.

Hernandez certainly can develop into a Hector Neris or Kelvin Herrera-esque reliever who could be still utilized in the late innings, albeit in situations that aren’t as high leverage.

After all, the Royals may have that guy who can handle those high-leverage, closer situations in James McArthur, who’s been absolutely lights-out in the month of September.

The Royals desperately need bullpen depth and live arms that can strike out guys in bunches in the 6th-8th innings while minimizing the walks and home runs.

From May to July, Hernandez proved that he could do that. In addition, he could also recapture that form as well in 2024 if he can put in some work on his breaking pitch quality this offseason as well. The lack of a shutdown secondary pitch is holding him back from being an above-average to good reliever (I would say he’s an average one for now).

That’s what the Royals need right now from Hernandez.

However, he will have to prove in Spring Training that he has made those strides in his curve and slider development…

If not, he may not be in this Royals bullpen by 2025.

Photo Credit: David Butler II/USA TODAY Sports Images