2024 Brewers Positional Preview: Back-end of the Rotation

“Don’t cry because it's over. Smile because it happened.”

Surely, the author of that quote wasn’t addressing the Brewers’ three-headed monster in the rotation, but they might as well have been.

Corbin Burnes now resides in Baltimore, while Brandon Woodruff will spend most of his time on the trainer’s table this year. Adrian Houser was acquired by his old boss in the Big Apple, and Eric Lauer failed to garner Major League interest, signing with Pittsburgh on Thursday after a career-worst year.

Heck, even Wade Miley is “50-50” to be ready for Opening Day. So, who might fill the vacated innings behind Freddy Peralta and Colin Rea?

Jakob Junis
2023: 3.87 ERA, 96:21 K:BB in 86 IP; 40-4 G-GS

Contract: Signed through 2024, mutual option for 2025

Junis set career marks in 2023 in ERA (3.87), K% (26.2), K:BB (4.57), and fastball velocity (93.7 mph) while working primarily out of the bullpen for the first time in his career. Before 2023, the right-hander started 106 of his 128 games at the big league level, posting a 4.75 ERA while punching out 566 in 627 innings.

The big shift for Junis came in his initial year in San Francisco in 2022 when he ditched his 4-seam fastball in favor of a sinker. Hitters slugged .593 off his 4-seamer in 2021.

“[The Giants] were able to explain to me and show me the science of it," Junis told Brewer Fanatic’s Matt Trueblood. "So I just got a lot more comfortable throwing it right away and stuck with it.”

Junis altered his entire arsenal with the Giants, not just the fastball. The Illinois native increased slider usage from 39.9% in 2021 to 50.5% in 2022, followed by 62.5% last year, the fourth-highest in the majors.

The sinker-slider combination was effective against right-handed hitters, but lefties fared better, recording an .807 OPS against the right-hander. A late-season adjustment to the changeup could be the key to success as a starter facing lineups stacked with lefties. Junis threw the pitch 20% in August and September after throwing it just 6% in the first four months.

The Brewers hope Junis can carry his improvements from the bullpen into the rotation to be a stabilizing force on a staff filled with question marks.

Joe Ross
2023: 14 IP in SF organization

2021: 4.17 ERA, 109 SO in 108 IP in 19 GS w/ WSH before undergoing TJS

The former National returned from Tommy John surgery in 2023, tossing just 14 innings across eight games at the end of the year. Ross averaged 95.9 mph with his fastball upon his return, up from 93.5 mph in 2021, albeit in shorter stints. Akin to Junis, the Brewers hope Ross can carry the velocity jump from the bullpen into the rotation.

Though the Brewers are preparing Ross for a starting role, relief may be the best role for the veteran for two reasons. The 30-year-old could be compromised in his innings load in 2024 after throwing just 17 innings over the past two seasons and 125 over the past four. Additionally, Ross has significant platoon splits—lefties have carried an .844 OPS throughout his career, while righties have managed just a .654 OPS. Advantageously selecting spots with a string of righties could maximize Ross’ effectiveness.

But until then, Ross will compete for a spot in the Brewers’ uncertain rotation.

DL Hall (LHP)
2022-23 (MLB, bullpen): 4.36 ERA, 42:11 K:BB in 33 IP

2023 (AAA): 4.22 ERA, 70:30 K:BB in 49 IP

#93 overall prospect per Baseball America

The Brewers acquired the six-time top-100 prospect as a headliner in the blockbuster Corbin Burnes trade, hoping they can turn his talent into production at the Major League level. The 25-year-old threw 33 big league innings across the past two seasons with Baltimore, all out of the bullpen, striking out 42 and walking just 11.

It’s easy to see why the Brewers are optimistic about Hall - the southpaw boasts one of two 80-grade (20-80 scouting scale) fastballs among all prospects, alongside fellow Brewers’ prospect Jacob Misiorowski. His 95.6 mph fastball plays up due to his funky arm angle and elite extension. In his limited big league time last year, Hall graded out in the top quartile of all pitchers in xERA (expected ERA), xBA (expected batting average), average exit velocity against, whiff%, K%, hard-hit %, and ground ball%.

The talent is there, but in order for Hall to become a reliable rotation member, he must cut down on walks and avoid the injured list. The Georgia native walked 5.2 per nine innings in his Minor League career before improving in his limited big league time. And the man named DL has struggled to stay off the IL—he’s never reached 100 innings in a season.

The talented Hall may be the biggest wild card in the Brewers’ rotation in 2024.

Robert Gasser (LHP)
2023 (AAA): 9-1, 3.79 ERA, 166:50 K:BB in 135 IP

#98 overall prospect per Baseball America

Fellow left-handed prospect Robert Gasser appears ready for the show, leading AAA’s International League with 166 strikeouts in 2023. Acquired in the controversial Josh Hader trade, Gasser lacks top-of-the-rotation upside but carries the floor of an above-average reliever or back-end starter.

The southpaw works with a five-pitch mix, throwing a 4-seam fastball, sinker, slider, cutter, and changeup. The slider is his best pitch - one of the better pitches in the Brewers’ organization, but question marks remain beyond the breaker. For Gasser to reach his potential as a mid-rotation starter, he must develop the changeup or cutter to throw against opposite-handed hitters - righties batted .320 and .265 against the offerings, respectively.

Whether Gasser can prove their effectiveness this spring may dictate his role to begin the season.

Aaron Ashby (LHP)
2023: missed season due to shoulder surgery

2022: 4.44 ERA in 107 IP, 126:47 K:BB

The left-hander is gunning for a rotation spot this spring after missing last year with shoulder surgery, an operation to remove calcified muscle near his rotator cuff. Ashby returned to action on a rehab assignment in September but struggled, surrendering 14 runs and 14 walks in 7 innings while averaging just 92 mph on his fastball.

A new year brings newfound health for the 25-year-old, who has sat around 94 mph, reaching 96 in his initial spring outings. The most recent time Ashby was on a big league mound, he boasted a 26.5 K% (73rd percentile), 57.4 GB% (98th percentile), and 29.4 Whiff% (75th percentile). But beyond the quality stuff, questions abound.

With $19.5 million committed to Ashby over the next four years, the Brewers will likely play it cautious with the former top-100 prospect. Surely, the Brewers will place an innings limit on the lefty - Ashby has surpassed 110 innings just once in his professional career and tossed just seven in 2023. Also of concern is Ashby’s command - his 9.9 BB% in 2022 ranked in the 23rd percentile.

Though the Brewers are stretching Ashby out as a starter, he may be best suited for a relief role as he re-acquaints himself with Major League hitters. Doing so may boost his performance - his ERA is a full run lower while working out of the bullpen - and his health.

Janson Junk
2023 (MLB): 7.1 IP, 4 ER

2023 (AAA): 4.18 ERA in 140 IP, 94:44 K:BB

Acquired in the Hunter Renfroe trade, Junk spent most of the season in Nashville, where he threw the third-most innings in the International League. However, behind a respectable 4.18 ERA lie concerning peripherals, specifically a lack of strikeouts.

Junk, who averaged 92.1 mph on his fastball in AAA, sat 94 and touched 96 mph in his lone late-season relief appearance in Milwaukee. A move to the bullpen could unlock velocity for the journeyman right-hander.

A move to the bullpen could also allow Junk to pare down his five-pitch mix. Hitters slugged just .265 against his curveball, widely considered a quality offering throughout his time as a prospect. Could a velocity bump and heavy reliance on the curveball turn Junk from a depth starter to a big-league reliever? Don’t rule it out. But for now, the Brewers are preparing Junk for a starting role in Music City or Cream City.

The Brewers' dearth of established rotation members lends to their small-market creativity. The Crew could choose to piggyback starters, managing innings and maximizing effectiveness. Uncertainty abounds, but not without options.