Revisiting the trade that helped build two of baseball's best teams

On Feb. 9, shortly before pitchers and catchers were due to report to Spring Training, the Red Sox and Brewers swung a six-player trade. It wasn't a blockbuster by any means. But it has turned out to be one of the most impactful moves of the offseason.

All six players in the deal have contributed in the Majors this season. That's exceptionally rare. Since 2009, there have been just 29 trades featuring at least five MLB players. The last two-team deal to feature six or more MLB players was the high-profile swap that sent Juan Soto from the Padres to the Yankees in December 2023. Here, we're defining an "MLB player" as someone who played in the big leagues in the season immediately following the trade.

But, as we'll get to in a bit, there's not really a precedent for this sort of deal -- one that didn't involve an established superstar, or an All-Star, or even anyone close to that caliber. And yet, with fewer than three weeks to go in the regular season, the Brewers and Red Sox are sailing toward October. Both teams are among the best in baseball this year. The contributions that they've received from the players in this trade have been invaluable.

Here's a look back at the trade, its impact, and its unique place in recent history.

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

Red Sox

Durbin, 26, was an NL Rookie of the Year Award finalist with the Brewers in 2025. He seemed like an ideal fit to slide into the void left behind at third base by Alex Bregman, whose free-agency departure sent shockwaves throughout the organization.

After a slow start with the bat, Durbin has been one of Boston's best hitters for the better part of the past three-and-a-half months. Since June 1, he is slashing .283/.366/.434 with a 125 wRC+, benefitting from a trip to a private hitting coach in mid-May. He's in the running to win a Gold Glove Award, too.

Meanwhile, Monasterio and Seigler emerged as unlikely spark plugs behind Boston's improbable midyear renaissance. The scrappy infielders stepped up while more established players like Trevor Story, Isiah Kiner-Falefa and Roman Anthony spent much of the summer on the injured list.

Brewers

Harrison spent much of last summer at Triple-A Worcester after being acquired by the Red Sox as a part of the return haul from the Giants for Rafael Devers. Just two years earlier, the left-hander was the No. 23 prospect in baseball, per MLB Pipeline. But he pitched to a 4.39 ERA in 42 games (37 starts) through his first three MLB seasons, struggling to put it all together.

This year, though, Harrison has mostly been a different pitcher. Even amid recent struggles, he owns a 3.66 ERA with 134 strikeouts in 110 2/3 innings. His emergence solidified the Brewers' rotation behind Jacob Misiorowski despite injuries to two rotation cogs in Brandon Woodruff and Quinn Priester. He's flourished with his four-seam fastball -- a pitch that the Red Sox de-emphasized in favor of a cutter, but one that Milwaukee has encouraged him to throw.

Brewers president of baseball operations Matt Arnold said in February that Drohan was a "very big part" of the deal, and things have certainly played out that way. The right-hander has posted a 4.09 ERA while logging 114 1/3 innings in a versatile swingman/spot starter role in Milwaukee's bullpen, optimizing a six-pitch mix.

Then there's Hamilton, who has been the most valuable piece of the deal for Milwaukee, at least according to bWAR. He sure fits the archetype of a classic Brewers player, with elite baserunning and a pesky approach in the box that makes up for his undersized stature.

So, how rare is this?

This is where things get really interesting: There simply haven't been many trades like this in recent history.

Entering play on Tuesday, the six players dealt in February had accumulated 8.4 WAR this season, using Baseball Reference's version of the statistic.

• Brewers: Hamilton (1.7 WAR), Harrison (1.3), Drohan (0.6)
• Red Sox: Durbin (3.6), Monasterio (0.7), Seigler (0.5)

Since 2009, there have only been five other two-team deals involving at least five MLB players that have generated that much WAR in the season immediately following the trade. With three weeks to go in the 2026 season, it's not unrealistic that the Red Sox-Brewers six-player swap winds up as the third-most valuable trade on this list.

Let's run through the five other trades that it's chasing.

1) 14.6 WAR (Dec. 7, 2023)
Yankees got: Juan Soto (8.0), Trent Grisham (0.4)
Padres got: Michael King (4.1), Kyle Higashioka (1.4), Randy Vazquez (0.5), Jonny Brito (0.2), Drew Thorpe (0)

This isn't quite a fair comparison, because Soto was a bona fide superstar at the time of the deal -- a three-time All-Star who had already established himself as one of the game's best players ahead of his age-25 season. San Diego recouped plenty of pitching depth, headlined by King, who made 30 starts and pitched to a 2.95 ERA in a career-best season.

2) 11.3 WAR (Nov. 23, 2016)
Mariners got: Jean Segura (3.6), Mitch Haniger (3.2), Zac Curtis (0)
D-backs got: Taijuan Walker (3.1), Ketel Marte (1.4)

The D-backs flipped Segura when his value was highest, coming off a 2016 campaign that saw him lead the NL with 203 hits and garner down-ballot MVP votes. In return, they netted Walker -- a first-round pick by the Mariners in 2010 -- and Marte, who has since become one of the best players in franchise history. His first year in Arizona was actually his worst, both by bWAR (1.4) and OPS+ (88) in 73 games.

3-T) 9.3 WAR (Dec. 11, 2014)
Marlins get: Dee Strange-Gordon (4.4), Dan Haren (2.0), Miguel Rojas (1.2)
Dodgers get: Kiké Hernández (1.7), Austin Barnes (0.1), Andrew Heaney (0), Chris Hatcher (-0.1)

Strange-Gordon earned his first career All-Star nod in 2014, notching 176 hits while leading the Majors in stolen bases (64) and triples (12). He was even better the following season with the Marlins, rapping out 205 hits to lead to lead the NL with a .333 batting average. But L.A. made out well, too, acquiring two foundational pieces to their dynastic run in Hernández and Barnes, who became Clayton Kershaw's personal catcher.

3-T. 9.3 WAR (Dec. 9, 2011)
Athletics get: Jarrod Parker (3.8), Ryan Cook (2.6), Collin Cowgill (0.4)
D-backs get: Trevor Cahill (1.8), Craig Breslow (0.7)

Cahill, the headliner of this five-player deal, was an All-Star and finished ninth in AL Cy Young Award voting in the 2010 season. But Parker (3.47 ERA in 29 starts) and Cook (2.09 ERA in 71 games) were each better players in 2012, steering the Athletics to a 94-win campaign and an AL West title. We'd be remiss if we didn't say hello to Breslow, the architect behind February's Red Sox-Brewers swap as Boston's chief baseball officer.

5. 8.7 WAR (Dec. 17, 2011)
Reds get: Mat Latos (3.9)
Padres get: Yasmani Grandal (2.5), Yonder Alonso (1.5), Edinson Volquez (0.7), Brad Boxberger (0.1)

Latos owned a 3.37 ERA through his first 72 big league starts across parts of three seasons with the Padres prior to the deal. He was every bit as good with the Reds, while the Padres expedited their rebuild with a haul of MLB-ready prospects. As it turns out, all four players wound up having productive careers.