The Brewers announced a trio of moves today, including Jared Koenig’s placement on the 15-day injured list due to left forearm tendinitis. Milwaukee has selected the contract of left-hander Rob Zastryzny from Triple-A to take Koenig’s spot on the active roster, and to create a 40-man roster spot, outfielder Chris Roller was designated for assignment.
With a 1.66 ERA over 38 innings this season, Koenig is the latest in a long string of unheralded pitchers to suddenly emerge as key members of Milwaukee’s bullpen. After spending much of his career in independent leagues and the Australian Baseball League, Koenig didn’t even make his debut in affiliated baseball until he pitched for the Athletics’ Double-A affiliate in 2021, and he made his MLB debut in the form of 39 1/3 innings of 5.72 ERA ball with Oakland in 2022. He then spent 2023 with the Padres’ Triple-A squad before being released, and he signed a minors deal with the Brewers last November.
Milwaukee selected Koenig’s minors deal to the big league roster in mid-April, and while he was optioned a couple of times, the southpaw has remained on the 26-man since the start of May since he was simply pitching too well to demote. Koenig’s 89.7% strand rate and .238 BABIP are doing a lot of the heavy lifting on that ERA, but his 3.42 SIERA is still more than respectable, and generated by a 49.5% grounder rate and above-average strikeout and walk numbers. Koenig’s sinker has a modest 94.5mph average velocity, but it quickly become a devastating pitch that has limited hitters to a .276 wOBA this season.
The 30-year-old’s breakout year has now unfortunately been halted by this injury, which Koenig told reporters (including Todd Rosiak of the Milwaukee Journal Sentinel) has been an issue “for the last few weeks.” He’ll receive an MRI on Monday to determine the extent of any damage, though Koenig’s feeling is that the team’s medical staff “are not overly concerned” for now.
With Koenig sidelined, the Brewers will replace him with another left-hander signed to a minors deal in the offseason. Zastryzny is a veteran of five MLB seasons, pitching with the Cubs from 2016-18 and then with the Mets, Angels, and Pirates in 2022-23, as those two stints were sandwiched around a three-year gap of time in the minors and the canceled 2020 minor league seasons. Zastryzny has a 4.70 ERA over 59 1/3 innings and 45 total appearances in the Show, including his 4.79 ERA in 20 2/3 innings with Pittsburgh last season.
The numbers have been better at the Triple-A level for Zastryzny over the last few seasons, with a particular spike upward in his time with the Brewers’ Triple-A affiliate — a 3.18 ERA, 34.2% strikeout rate, and 7.2% walk rate in 28 1/3 innings in Nashville. It will be interesting to see if this production can carry over to the majors and whether or not the Brewers might’ve revived another pitcher, as Zastryzny joins Bryan Hudson and Hoby Milner as the left-handed options in Milwaukee’s bullpen.
The 27-year Roller was a 30th-round pick for the Dodgers in the 2017 draft, and his long road in the minors finally resulted in a cup of coffee in the Show this season. Roller appeared in a single game for the Brewers, pinch-hitting and playing three innings as a defensive sub in center field in Milwaukee’s 10-2 win over the Pirates on May 15, before being optioned back to Triple-A a few days later.
Roller has been in the Brewers’ organization since Milwaukee acquired him in a trade with the Guardians last August. The 27-year-old’s Triple-A performance has been pretty respectable over his career, though it has been dragged down by a .201/.238/.321 slash line in 168 PA with Nashville this season. It was enough for the Brewers to decide make Roller the odd man out of the roster mix, so he’ll now be exposed to the DFA wire before Milwaukee can potentially outright him off the 40-man.