The 2026 World Series matchup is set. The Milwaukee Brewers will take on the Tampa Bay Rays, with this year's Fall Classic crowning a first-time champion.

Five former St. Louis Cardinals will be competing for a chance at baseball's ultimate glory. Two of them are playing for the Brewers and three for the Rays. No matter the result, multiple former Cardinals will be celebrating a championship in the next couple of weeks.

Barring injuries, there shouldn't be too many changes to both the Brewers and Rays rosters in the World Series. Rosters should be announced the morning of Game 1, which will be on October 23.

Former Cardinals on the Milwaukee Brewers

Both former Cardinals that will be playing for the Brewers in the World Series are right-hander Dustin May and left-hander JoJo Romero. Both pitchers were traded to Milwaukee at the trade deadline this season.

May was a free-agent signing for this season, landing a $12.5 million deal. Romero came to St. Louis in the Edmundo Sosa trade with the Phillies back in 2022. Both pitchers were impending free agents, and unlikely to receive the $23.15 million qualifying offer, so they were shipped off to their division rival for a pair of hitting prospects.

For both Romero and May, the Cardinals got outfielders Josiah Ragsdale and Alexander Frias in the trade. Ragsdale was a breakout slugger in the Brewers' Double-A affiliate in Biloxi, while Frias was a teenager who flashed in the Arizona Complex League before heading to Class A. The Cardinals believed in their breakout, targeting both prospects in their deadline sell-off.

May and Romero have been on the Brewers postseason roster. Romero has a 1.69 ERA in four postseason outings. May has started Game 3 of the NLDS and used as a bulk reliever for Game 4 of the NLCS. Both pitchers should be on their World Series roster.

Former Cardinals on the Rays

The Rays don't feature any players who played for the Cardinals in 2026. But there are three former players on their roster.

Steven Matz is the highest profile of the three players. The left-hander signed a four-year contract after the 2021 season. He pitched for St. Louis in the 2022-2025 seasons before getting dealt to the Boston Red Sox at last year's deadline. Matz signed a two-year deal with the Rays before this season.

Richie Palacios and Ryan Vilade were Cardinals for the briefest of times. Palacios was picked up for cash considerations in 2023. He was later dealt to the Rays in exchange for reliever Andrew Kittredge later that season.

Vilade was a former Rockies prospect who flamed out with multiple organizations. He had a stop in Detroit before coming to St. Louis. After going 1-for-13 in seven games, Vilade was designated for assignment. He was claimed off waivers by the Cincinnati Reds. The Rays acquired him in a trade for cash in November.