Cardinals-Red Sox Complete Trade to Bring 6'7'' Lefty to St. Louis

The St. Louis Cardinals have made their first splash of the offseason so far.

Jul 17, 2026; Boston, Massachusetts, USA; Boston Red Sox pitcher Eduardo Rivera (99) pitches during the first inning against the Tampa Bay Rays at Fenway Park. Mandatory Credit: Bob DeChiara-Imagn Images | IMAGN IMAGES via Reuters Connect

The St. Louis Cardinals and the Boston Red Sox have shown that they aren't afraid to swing trades with one another over and over again.

Last year, the Cardinals traded Willson Contreras and Sonny Gray to the Boston Red Sox in separate trades. Then, there were rumors that Boston was interested in Brendan Donovan as well before he was traded to the Seattle Mariners. The 2026 offseason is still new, but the Cardinals and Red Sox have wasted no time coming back together on a deal. On Tuesday, Andrew Parker of SoxProspects.com reported that the Cardinals have acquired 6'7'' lefty Eduardo Rivera from Boston in exchange for right-handed pitcher Juan Garcia.

"Another Red Sox trade: LHP Eduardo Rivera has been traded to the St. Louis Cardinals in exchange for minor league RHP Juan Garcia, I’m told," Parker wrote.

Cardinals Land Eduardo Rivera From Boston

Apr 22, 2026; Boston, Massachusetts, USA; Boston Red Sox relief pitcher Eduardo Rivera (99) pitches against the New York Yankees during seventh inning at Fenway Park. Mandatory Credit: Eric Canha-Imagn Images | IMAGN IMAGES via Reuters Connect

The Cardinals and Red Sox have struck once again. Rivera is a very intriguing addition for St. Louis. He has great size at 6'7'' and 237 pounds. He features a blistering fastball that approaches triple digits. Plus, he's still just 23 years old. This is a guy who made his big league debut in 2026 and pitched in four games for Boston with a 6.30 ERA. He pitched in 26 games down in the minors and had a 2.59 ERA and a 71-to-30 strikeout-to-walk ratio in 55 2/3 innings pitched. In Triple-A specifically, Rivera had a 2.96 ERA in 24 appearances, including three starts.

While in the majors, Rivera made three starts in four appearances. While down in the minors, he made five starts in 26 total appearances.

The Cardinals are getting a big lefty with a good fastball who can help the club right away in the bullpen. Or, he could even be a rotation option if St. Louis sees fit. But the most likely option is going to be using him as a reliever. Rivera is still technically a rookie as well, so he has years of control ahead. This is a good move right away from Chaim Bloom and the Cardinals' front office.

Cardinals Trade Away Juan Garcia

Apr 21, 2025; Atlanta, Georgia, USA; A St. Louis Cardinals hat and glove in the dugout against the Atlanta Braves in the first inning at Truist Park. Mandatory Credit: Brett Davis-Imagn Images | IMAGN IMAGES via Reuters Connect

To get a player who can help St. Louis in the big leagues right now, all it had to do was give up an 18-year-old lottery ticket. Garcia made 11 starts in the Dominican Summer League in 2026 and logged a 4.40 ERA in 43 innings pitched. He's still far too young to know if he's ever going to make an impact in the majors. But the Cardinals got a guy who can help right now in exchange.