Brewers Minor League Relief Pitcher of the Month: June 2024

[Spencer Michaelis]

We continue our MiLB Player of the Month series with June's top five relief pitchers. 

Image courtesy of Neal Hock, Carolina Mudcats

The Brewers' minor league pitching was very impressive on the starting side, and the relievers had many strong candidates as well.

Beginning with a couple of honorable mentions:

HONORABLE MENTIONS
RHP - Dikember Sanchez - ACL Brewers and Carolina Mudcats - 5 G, 11.2 IP, 0-1, 2.31 ERA, 4.44 FIP, 1.03 WHIP, 7 H, 5 BB, 14 K, 1 SV

RHP - Craig Yoho - Biloxi Shuckers - 8 G, 11 IP, 1-0, 2.45 ERA, 0.29 FIP, 1.00 WHIP, 7 H, 4 BB, 23 K
He’s human, after all. One lousy outing, in which he allowed three earned runs in one inning, cost Yoho a spot on the list, but everyone has had the chance to read about him numerous times. He wanted to give some new names a chance to shine.

---

TOP FIVE RELIEF PITCHERS FOR JUNE
#5 RHP - Nick Merkel - Biloxi Shuckers - 7 G, 15.1 IP, 1-0, 1.76 ERA, 3.64 FIP, 0.78 WHIP, 7 H, 5 BB, 18 K
Unranked by all publications

Merkel was signed as an undrafted free agent in 2022 out of Central Methodist University, an NAIA school in Missouri. Checking in at 6’7 and weighing 255 pounds, Merkel has a fitting nickname, “Large Mammal,” that he even uses for his Twitter handle. Merkel moved quickly from Low-A to High-A last year and was assigned to Double-A to begin this season.

While his size might give the impression of a fireballer, his fastball only sits in the low 90s, touching 93 at times. He appears to cut the fastball and run it at other times. It does a good job getting swing-and-miss when cut and gets grounders either way.

He throws two breaking balls for his secondaries. His low-80s sweeping slider has been a great pitch against left-handed hitters. His upper 70s knuckle curve has a lot more depth to it, and he uses that more against right-handed hitters than he does against lefties.

In June, Merkel did something very few pitchers could do. He was generating a ton of ground balls and a ton of whiffs. He posted a ridiculous 41.4% whiff rate, placing him in the 99th percentile for the level. While his walks were in a reasonable place in June, he hit four batters, so he was issuing free passes at a pretty high rate. At the same time, he generated ground balls at a 60% clip, which was in the 95th percentile for Double-A pitchers with at least ten innings in June, which helped him work around those free passes.

Merkel is 26 years old, and shows signs of the peripheral numbers you are looking for in a middle reliever. He might be in line for a promotion to Triple-A at some point in the second half, even if the surface numbers might not blow anybody away.

---

#4 LHP - Aaron Rund - Wisconsin Timber Rattlers - 8 G, 11.1 IP, 1-1, 1.23 ERA, 2.69 FIP, 0.89 WHIP, 7 H, 6 BB, 15 K
Unranked by all publications

Rund went undrafted in the 2023 draft out of Campbell University. After playing half a season with the Florence Y’alls of the Frontier League, he signed with the Brewers this past offseason. The recently turned 25-year-old has been in high-A all season and has pitched to a 1.32 ERA.

Coming from a low, three-quarters arm slot that borders on being sidearm, Rund is a sinker-baller who mainly aims to get the ball on the ground. Sitting 93 on his fastball and getting up to 95, the pitch does what it intended, as his 55.7% ground ball rate for the season places him in the 93rd percentile for High-A.

In terms of secondaries, Rund uses his slider the most often. The pitch sits in the 85-86 MPH range and mirrors his fastball well, giving hitters a long tail to worry about between the two pitches. He also throws an upper-70s curveball that is used less often but gives hitters another velocity band to worry about. At times, he appears to blend those two into a low-80s slurve. Based on how the catcher throws down signs, those are meant to be the slider.

In June, Rund was great at what he’s usually good at. He didn’t generate hardly any swing and miss (1st percentile whiff rate), but he did land a ton of pitches for strikes, back-dooring sinkers, and landing breaking balls on corners. His called-strike rate of 36.8% was in the 96th percentile. He also improved his already strong ground ball rate, reaching 59.5% in June. There was minimal hard contact, and even when hitters did get one on the barrel, it was usually on the ground.

Rund is 25 and posting an ERA of 1.32 so far at High-A. While he doesn’t have the stuff to be a closer down the road, he does have qualities that go a long way for a middle reliever. He will likely see time at Double-A at some point this season.

---

#3 RHP - Chase Costello - Wisconsin Timber Rattlers - 7 G, 10 IP, 3-0, 1.80 ERA, 1.81 FIP, 0.90 WHIP, 6 H, 3 BB, 13 K
Unranked by all publications

Costello was another player brought into the organization out of independent ball, signing before the 2023 season. He spent time at LSU, St Thomas, and Stetson during college, eventually going undrafted and signing with the Boise Hawks of the Pioneer League. He had a solid, if unspectacular, season in Carolina last year and has carried over similar results to the 2024 season with the T-Rats.

 Unlike many indy ball signees, Costello was only 22 years old when he signed and is currently 24. His fastball sat in the 92-94 range in college but is now sitting 94-95 and touching 96 at times. It has a decent arm-side run, and he commands it relatively well. 

He also throws a changeup in the 82-84 range, which is probably his best pitch for generating swing and miss, though his command of the pitch comes and goes. His third pitch is a short slider in the 86-87 MPH range, though it lags behind the other two pitches and lacks consistency in movement and command.

Costello mostly used his top two pitches in June to keep hitters off balance. His 36.5% whiff rate placed him in the 89th percentile at the level among pitchers who threw at least ten innings in June. His 36.1% strikeout rate put him in the 93rd percentile. He did have some batted-ball luck, and his outfielders showed up for him on a couple of run-saving plays in June, but his ability to generate swings and misses is what carried him to such a strong month.

Costello is unlikely to move from High-A too soon, but if his June performance is a sign of things to come, he’s a name Brewers fans will want to keep an eye on.

---

#2 RHP - Blake Holub - Biloxi Shuckers - 8 G, 10 IP, 1-0, 0.00 ERA, 1.18 FIP, 0.70 WHIP, 5 H, 2 BB, 14 K, 5 SV.
Unranked by all publications

Acquired in the Mark Canha trade this past offseason, Holub is the fourth pitcher on this list to take an irregular path to pro ball. Holub was a two-way player at Division II St Edwards University in Texas before the Tigers selected him in the 15th round in 2021. Holub began the year with Triple-A Nashville. Unfortunately, things didn't go well there, and he was sent down to Double-A in mid-May. He took that demotion as well as one can and had not allowed a single run at the level through the end of June.

Coming from a very high, over-the-top slot, Holub has a fastball that sits in the mid-90s and has decent carry on it, along with a few inches of cut. He also adds seven feet of extension, which helps the velocity play up a bit higher. The Vertical Approach Angle is -5.6 in his Triple-A appearances, which means the carry he gets on the pitch doesn’t play up much, but it has been a solid pitch for him.

His slider sits around 82-84 MPH and has decent characteristics, though it has been hit around a bit at the Triple-A level. He did not use his mid-80s splitter very often in Triple-A, but when he did, it was a fantastic pitch, and the characteristics grade out very well. He went to it more often in Double-A and reaped the benefits of that.

Holub generated whiffs at a 42.9% clip in June, placing him in the 99th percentile for Double-A pitchers with at least ten innings pitched. His swinging strike rate of 21.2% was in the 98th percentile, and his overall strikeout rate placed him in the 96th percentile at 36.8%. Not only did he miss a lot of bats, but he also generated ground balls at a 54.5% rate, putting him in the 90th percentile.

Holub got promoted back to Triple-A to begin July and allowed two earned runs in his first inning there. Something about that jump from Biloxi to Nashville is giving him problems, but he has shown he is above Double-A and should get ample opportunity to find his footing with the Sounds.

---

#1 RHP - Aidan Maldonado - Carolina Mudcats - 9 G, 16 IP, 0-0, 0.00 ERA, 1.59 FIP, 0.44 WHIP, 6 H, 1 BB, 19 K, 2 SV.
Unranked by all publications

The Brewers 14th round selection in the 2022 draft out of the University of Minnesota, Maldonado was garnering some attention early in the spring of 2023 with his array of offspeed offerings. He got off to a strong start with Carolina but dealt with injuries and some ineffectiveness the rest of the way. A starter to begin the 2023 season, Maldonado has moved into a full-time relief role in 2024.

His fastball is in the 92-94 range but seems to get on hitters more than the velocity would lead you to believe. Maldonado is a big-time “drop and drive” pitcher, and he gets really low into his back leg, causing the fastball to come out from a low slot and have strong carry through the zone. His delivery is also “herky-jerky” and has to be a tough sightline for hitters in the box, which also helps the pitch play up.

Maldonado has leaned more on his curveball and changeup this year than he did last year. His curveball is an upper-70s offering with a good amount of depth. He seems comfortable landing it for strikes. The changeup sits in the low-80s and has a lot of sharp movement to the arm side and good depth. The changeup is the best offspeed offering he has.

Maldonado has also thrown a slider at times. While he seems to struggle with the command, it would serve him well to use it more often, as it has good movement and sits in a different velocity band than the curve and changeup, coming in around 85-86.

However, Maldonado didn’t need to use the slider too often in June. His three-pitch mix was done this month, as he struck out 19 hitters to only a single walk. That K: BB ratio put him in the 99th percentile for his level. Interestingly, despite his high strikeout total, he only generated whiffs at a 25.4% clip, the 30th percentile. He did land several pitches for strikes and had the second-highest foul ball rate at the level. When the ball did get put in play, it was often on the ground, as evidenced by his 58.8% ground ball rate.

At 24 years old, Maldonado seems ready for the challenge of High-A, as even when the surface numbers weren’t great early on this season, his peripherals were in a very good place. 

Thanks for following along with this three-part series on the Brewers' minor league system. Let us know your thoughts below! Did we miss anybody?

View full article

[dsid74]

That is some funky delivery by Maldonado.  It appears he tunnels his pitches well and batters don't see that delivery from many (if any) other pitchers.  Those batters looked totally over matched.  Will be interesting to see if that deception plays at higher levels.  And if after seeing him a number of times if batters will successfully adjust.  This kid is worth keeping tabs on.

[Joseph Zarr]

Can confirm: 

Maldonado continued looking filthy against Low-A hitters again tonight. His move North is imminent. Let's get him into a more age-appropriate environment now that he has started matching final results to the arsenal he possesses. At one point, in the ninth inning, he had the Fred Nats announcers saying: "What was that off-speed offering? Was that a splitter?" on a nasty right-to-left swinging K. Yeah, his change-up hit on another level tonight. Gooooood stuff. His heater actually reminds me of early RHP Logan Henderson ride and rise.