The Boston Red Sox have completed their third trade of the offseason alraedy and it is still just Nov. 3, as of writing.

Boston had to get busy right away to kick off the offseason. The reason why this is the case is because Boston needed to get its 40-man roster into compliance. The club had to reinstate players from the 60-day Injured List by Monday, so, they had to free up the roster spots to do so. Before Monday, that led to trades centered around Nate Eaton and Tsung-Che Cheng. Eaton went to the Athletics and Cheng went to the Detroit Tigers. On Monday, the Red Sox opted to designate Eduardo Rivera for assignment because they were unable to get a trade done before the 40-man roster deadline.

When a player is designated for assignment, other clubs have a chance to place a waiver claim on said player. But, the club that does the DFA-ing also still has a chance to trade the player initially. Boston capitalized on Tuesday by trading Rivera to the St. Louis Cardinals in exchange for 18-year-old reliever Juan Carlos Garcia.

Why Trade Eduardo Rivera?

Rivera, the 6'7'' lefty, made his big league debut in 2026 and pitched in four games in the majors, including three starts. The lefty had a 6.30 ERA in the majors. In Triple-A, he had a 2.96 ERA in 24 appearances, including three starts, across 45 2/3 innings pitched. Rivera is a lefty who would've given the Red Sox another left-handed bullpen option to work with. But there were difficult decisions to make.

The Red Sox could've easily designated Raymond Burgos for assignment if they saw fit. But they opted to move on from Rivera instead. That could be viewed as a sign of belief in Burgos.

Who Is Juan Carlos Garcia?

The Red Sox are getting an 18-year-old lefty that they can now try to mold into a hurler who will help the club in the future. Garcia has good size at 6'2'' and 187 pounds. He made his professional debut in the Dominican Summer League in 2025. He logged a 3.40 ERA in 12 appearances across 47 2/3 innings pitched. In 2026, he pitched in the Dominican Summer League again and logged a 4.40 ERA in 11 starts across 43 innings of action.

He's a righty and won't turn 19 years old until May 30. After the deal, it's likely going to be a long time before you hear much about Garcia again. But he's joining a farm system that has gotten very good at developing pitchers. Now, Boston has another young guy to try to work with.