The Red Sox have officially sent Eduardo Rivera to the Cardinals, completing a move that came after Boston designated him for assignment on Monday while sorting out its 40-man roster.
Rivera, who was taken in the 11th round of the 2021 draft, had put together several strong minor league seasons but never quite found his footing in his first extended look in the majors this past year. Boston simply didn’t have room to keep him, and St. Louis will now get a chance to see what he can do in a bullpen that has less certainty, especially on the left side.
The 23-year-old spent time as both a starter and reliever while climbing through the Red Sox system. He began the 2026 season at Double-A, where he gave up one run across two starts before earning a promotion to Triple-A. At Worcester, he logged a 2.96 ERA in 45 2/3 innings, with most of that work coming out of the bullpen.
Rivera’s first big-league appearance came in late April, when Boston used him to cover innings against the Yankees. He responded with 3 1/3 scoreless frames in his MLB debut, but that wasn’t enough to secure a long stay on the roster.
His next chance didn’t come until July, when he started against the Mets shortly before the All-Star break and threw 3 2/3 scoreless innings. Things went sideways after that, as he was charged with seven earned runs over his final two outings, and a lumbar strain ended his season in mid-August.
Going back the other way, St. Louis is adding Garcia, an 18-year-old left-hander it signed as an international free agent out of Mexico in 2025.
He has spent the last two seasons in the Dominican Summer League. In 2026, Garcia posted a 4.40 ERA in 11 starts, didn’t rack up many strikeouts, and walked just 10 batters over 43 innings.
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Red Sox Just Made A Trade Fans May Second Guess Later
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