Two days before pitchers and catchers report for Spring Training, the Brewers added a key new arm.
Milwaukee landed left-hander Kyle Harrison in a six-player trade with the Red Sox on Monday, the teams announced. The Brewers will also get infielder David Hamilton and pitching prospect Shane Drohan in the deal.
The Brewers are shaking up their infield in the process. They're sending a trio of infielders to Boston -- National League Rookie of the Year finalist Caleb Durbin, Andruw Monasterio and Anthony Seigler -- along with a 2026 Competitive Balance Round B Draft pick.
TRADE DETAILS
Red Sox receive: INF Caleb Durbin, INF Andruw Monasterio, INF Anthony Seigler, Competitive Balance Round B Draft pick
Brewers receive: LHP Kyle Harrison, INF David Hamilton, LHP prospect Shane Drohan
Harrison is a high-upside arm who was one of the key pieces of the Red Sox and Giants' Rafael Devers trade last season. The 24-year-old was San Francisco's former No. 1 prospect and helped the Giants land the All-Star Devers.
Now the young southpaw comes to Milwaukee, where Harrison could help boost a starting rotation that sent Freddy Peralta to the Mets a few weeks ago. After Brandon Woodruff, the Brewers have a lot of promising but unproven starters entering Spring Training -- a list that includes Jacob Misiorowski, Quinn Priester, Robert Gasser, Logan Henderson, Brandon Sproat and now Harrison.
Harrison could also pitch out of the bullpen if the Brewers need him there, as Harrison has experience both as a starter and a reliever in the big leagues.
Last season, Harrison pitched in 11 games (six of them starts) for the Giants and Red Sox. He went 1-1 with a 4.04 ERA and 38 strikeouts in 35 2/3 innings (9.6 K/9). The two years before that, he pitched exclusively as a starter in San Francisco, and in those 31 starts, he went 8-8 with a 4.47 ERA and 153 strikeouts in 159 innings (8.7 K/9).
Harrison throws five pitches -- a four-seam fastball, sinker, cutter, slurve and changeup -- but he relies primarily on his four-seamer and slurve.
His fastball was his best pitch last season, averaging 94.6 mph with 14 inches of arm-side run -- both above-average velocity for a lefty and above-average movement -- while generating a strong 26% swing-and-miss rate. The heater is his No. 1 strikeout pitch, with 133 of Harrison's 191 strikeouts in the Majors coming on his four-seamer.
The Brewers' trade Monday will also be a reunion with Hamilton, who was originally a Milwaukee Draft pick. The Brewers took Hamilton in the eighth round in 2019, but they traded him to the Red Sox two years later in the deal that brought Hunter Renfroe to Milwaukee.
Now that he's back with the Brewers, Hamilton could get a crack at taking some of the third base reps left open by sending Durbin, Monasterio and Seigler to Boston.
Trading those three players all at once instantly makes the question of "Who will play third base for the Brewers in 2026?" a big storyline entering Spring Training. Durbin in particular is a big loss at the hot corner after his promising rookie season, which saw him emerge as the Brewers' everyday third baseman, including for their postseason run, and finish third in NL Rookie of the Year voting.
Hamilton is just one possible answer. He's a versatile fielder, which the Brewers will no doubt try to take advantage of.
While the 28-year-old has played mostly second base and shortstop in the Majors, the Brewers hope Hamilton's ability in the middle infield can translate to third base -- just like it did with Durbin, who played mostly second base in the Minors but seized Milwaukee's starting job at third after his callup.
Hamilton isn't as strong of a hitter as Durbin -- he batted just .198 with six home runs and a .590 OPS in 194 plate appearances last season -- but he is an excellent speedster. He had 22 stolen bases in 91 games for the Red Sox in 2025, and 33 stolen bases in 98 games in '24. Hamilton posted an average sprint speed of over 29 feet per second in both seasons, according to Statcast, which places him right around the fastest 5% of MLB runners.
There are more interesting possibilities for the Brewers infield if Jett Williams, the centerpiece of their Peralta trade, is able to win a spot on the Opening Day roster. Williams, MLB's No. 51 overall prospect, could play shortstop, and Joey Ortiz could slide back to third base, where he played in 2024. Or Ortiz could stay at short and the Brewers could try to give Williams reps at third in Spring Training, hoping the same middle-infield-to-corner-infield path could work for him. That would leave Hamilton in a more utility role.
The last piece the Brewers are getting in their deal with Boston is the 27-year-old left-hander Drohan, who ranked as Boston's No. 30 prospect last season, per MLB Pipeline.
The 6-foot-3 Drohan spent the 2025 season at High-A and Triple-A, going 5-2 with a 3.00 ERA and 77 strikeouts in 54 innings over 15 games (14 starts). He missed about three months with forearm inflammation but was excellent at Triple-A when healthy (2.27 ERA and 67 K's in 47 2/3 innings at that level).
Drohan's fastball averages 93-94 mph and can touch 96, and he has a swing-and-miss mid-80s slider, plus an upper-70s curveball, mid-80s changeup and high-80s cutter.