The Milwaukee Brewers won their first World Series championship, taking down the Tampa Bay Rays in five games. That completed one of the most dominant seasons by any team since the start of the Wild Card era in 1995. The Brewers led MLB with 103 wins in 2026, then went 11-2 in the postseason to seal the deal.

The Brewers would not have gotten there without making some excellent trades along the way. Here are the five major trades that shaped their championship roster.

Brewers Join Three-Team Trade, Steal World Series MVP from NL Rival

After the 2022 season, the Brewers were able to sneak into a trade and land their future World Series MVP from a National League rival. David Stearns was still leading their baseball operations department, although Matt Arnold had already been elevated to his general manager position.

The Atlanta Braves were looking to upgrade the catching position, targeting Sean Murphy from the then-Oakland Athletics. That meant that William Contreras, a 2022 All-Star, suddenly became available.

The Brewers hopped into the trade, looking to upgrade the catcher position themselves. While Murphy was the headlining player in the three-team deal, Milwaukee ultimately got the best player. It cost them catcher Manny Piña and outfield prospect Esteury Ruiz. In addition to Contreras, they got reliever Joel Payamps and a pitching prospect in Justin Yeager.

The deal could not have gone better for the Brewers. Contreras was viewed as a bat-first catcher at the time and not a good defender. That has since changed, as he's now one of the premier catchers in MLB. In four seasons with Milwaukee, he's slashing .275/.354/.442 with 75 home runs and 15.3 bWAR.

He was named an All-Star in 2026 and then the World Series MVP. Contreras is under team control for the 2027 season before becoming a free agent.

Controversial Josh Hader Trade Finally Bears Fruit in 2026 Postseason

The Brewers had one of the best closers in baseball in Josh Hader. But they elected to sell high on Hader, a controversial decision, despite being in the thick of Wild Card contention. The package of players coming back from San Diego included Taylor Rogers, Dinelson Lamet, Esteury Ruiz, and Robert Gasser.

The only player in that deal that stuck around and made any impact was Gasser. The left-hander broke through in 2026, making 21 appearances (20 starts) in the regular season. He got an opportunity to join the rotation, as Kyle Harrison struggled down the stretch, and made the most of it.

In three postseason starts, he allowed just one run in 15 innings. All three of his appearances came on the road, which meant he expertly handled two hostile environments in the postseason. No player improved their standing in the organization more in the postseason than Gasser.

Bobby Diesel enters the 2027 season with his rotation spot secured. Depending on how well Harrison rebounds, Gasser projects as Milwaukee's No. 4 starter in a rotation full of starters with many years of team control.

Brewers Landed Their Closer for Next to Nothing

Trevor Megill was a talented arm that just needed the right opportunity. That came in 2023, when the Brewers acquired the 6'8" right-hander from the Minnesota Twins for cash considerations and a player to be named later (Taylor Floyd).

Megill had plenty of velocity, sitting 98-100 MPH from a high slot and good carry. He paired that up with an 89-90 MPH knucklecurve that sits in the deathball shape.

In his second season with the club, Megill earned the closer role. In three seasons in that role, Megill has a 2.61 ERA, 81 saves, and a 2025 All-Star selection. He also recorded the final six outs of the 2026 World Series.

Brewers Get Postseason Unsung Hero, Future No. 2 Starter from Red Sox

The Brewers made an excellent trade in February, turning infielders Caleb Durbin, Andruw Monasterio, and Anthony Seigler into Kyle Harrison and David Hamilton. Milwaukee will ultimately get the better end of the deal long-term, although it worked out for both clubs in the first season.

Harrison was a talented arm who struggled to get the right results relative to his abilities with the Red Sox and Giants. A couple of minor tweaks unlocked the left-hander's potential, as he was buzzsawing lineups in the first half of 2026. While he struggled to close out the season and ultimately didn't appear in the postseason, every start mattered in getting the Brewers in position to dominate in October.

If Harrison can rediscover what worked in the first half of 2026, the Brewers may have another All-Star to pair up with Jacob Misiorowski. It will be a matter of also attempting to prevent what happened in the second half from recurring, so the full-season results finally match the talent instead of flashing.

Hamilton was a utility infielder that settled into the strong-side platoon role at third base. He got a lot of run in the postseason, especially in the World Series. In his first-ever postseason, he slashed .333/.357/.593 with two home runs.

Hamilton may eventually lose his spot on the roster in favor of top prospects Jesús Made and Luis Peña, but he gives them a professional player until that day arrives.

Intradivision Trade Provides Final Touches on Championship Squad

The final trade that shaped this roster was the deal that Matt Arnold made at the deadline. In a rare intradivision deal, he acquired impending free agents Dustin May and JoJo Romero from the St. Louis Cardinals. Milwaukee sent outfield prospects Josiah Ragsdale and Alexander Frias to the Cardinals.

May fell short of expectations somewhat, as he was unable to secure the fourth starter role. But the Brewers still trusted him enough to keep running him out there. He pitched as both a bulk reliever and a short-burst guy. His ERA is unsightly because he surrendered seven runs in his three bulk outings, but he pitched scoreless baseball in his two more traditional relief appearances.

Romero was indispensable. While not a leverage arm, he served as a steadying presence in the bullpen. He allowed one run in eight innings with 11 strikeouts. He stepped up multiple times in the World Series, including filling in for an injured Jacob Misiorowski in Game 5.