With the Red Sox‘s 2026 season ending in the AL Wild Card round, their focus has turned to 2027. But the MLB postseason has rolled on.

The 2026 World Series matchup is officially set, with two elite small-ball, pitching-oriented squads facing off in Brewers vs. Rays. 

For Red Sox fans tuning into the Fall Classic, there are four names that may stick out among the rest between Milwaukee and Tampa Bay’s rosters.

Here are the four former Red Sox players set to play in the 2026 World Series.

Former Red Sox Players in 2026 World Series

There are four players who had stints with the Red Sox who will have a chance to win a ring this year: two Rays, and two Brewers.

Cam Booser, RP, Rays

In 2023, the Red Sox took a shot on a pitcher who had spent time in the Twins organization, but retired after being suspended, then had stints in independent leagues. Cam Booser was invited to spring training in 2024, and he made his way onto Boston’s roster.

After finishing the 2024 season with a 3.38 ERA and 43 strikeouts in 43 relief appearances for the Red Sox, the left-hander was traded to the White Sox in the offseason. He landed with the Rays in free agency on a minor-league deal after the 2025 season — and it’s proved to be an excellent deal for Tampa Bay.

Over 42 game appearances in 2026, Booser pitched to a 1.98 ERA and 45 strikeouts, becoming one of Kevin Cash’s most trusted arms. He’s remained one of the top options in the Rays’ bullpen in the postseason.

Cam Booser stepped away from baseball in 2017 to become a carpenter. Tonight, he made his Major League debut. What a moment https://t.co/GKhGNuGdCz

— Baseball Quotes (@BaseballQuotes1) April 20, 2024Steven Matz, RP, Rays

Former Mets prospect and starting pitcher Steven Matz landed with the Red Sox in July 2025, traded to Boston in exchange for Blaze Jordan before the trade deadline. As a reliever, Matz then made 21 appearances for the team, a top bullpen option with a 2.08 ERA with 12 strikeouts and one save across 21.2 innings pitched.

Matz, however, left Boston for Tampa Bay last offseason, agreeing to a two-year, $15 million contract. Initially, he joined the Rays as a starter. But Matz struggled in that role, moved to the bullpen after starting out with a 5.48 ERA across his first 10 starts of the season.

Since then, Matz has settled in a bit more, but hasn’t established himself as a top bullpen arm for the Rays.

David Hamilton, INF, Brewers

While the Brewers drafted infielder David Hamilton in the 2019 MLB Draft, the Red Sox acquired him in the December 2021 Hunter Renfroe deal that also sent Jackie Bradley Jr. and Alex Binelas to Boston.

Hamilton was promoted to the big leagues for the first time in June 2022, but bounced between the Red Sox and Triple-A throughout the season. Known for his strong defensive capabilities and speed, he went on to steal 33 bases in 2024 and 22 in 2025.

However, Hamilton wound up being traded back to his original organization after three full seasons with the Red Sox. Last offseason, Boston sent Hamilton, Kyle Harrison, Shane Drohan to Milwaukee in exchange for Caleb Durbin, Andruw Monasterio, Anthony Seigler and a compensation pick.

In 2026, he’s emerged as an excellent small-ball player for the Brewers, stealing 30 bases and even hitting a home run off Edwin Diaz in the NLCS. 

DAVID HAMILTON WITH AN EXCLAMATION POINT! https://t.co/B7yc11dBLs

— MLB (@MLB) October 16, 2026Kyle Harrison, SP, Brewers

Harrison was also part of last offseason’s Brewers-Red Sox deal, spending just a few months in Boston after being included in the blockbuster Rafael Devers trade in June 2025. Harrison made just three appearances for Boston, recording a 3.00 ERA with 13 strikeouts across 12 innings pitched.

Last offseason, though, the Red Sox moved on, and Harrison joined the Brewers’ rotation. In 2025, Harrison started in 28 games with a 4.20 ERA, 141 strikeouts and an 11-5 record.

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