The Boston Red Sox traded left-hander Eduardo Rivera to the St. Louis Cardinals on Tuesday in exchange for minor league right-hander Juan Garcia.
Boston designated Rivera, 23, for assignment on Monday to reach the 40-man roster limit. He made his major league debut on April 22 and finished 0-1 with a 6.30 ERA in four games (three starts) for the Red Sox in 2026.
Rivera was 7-2 with a 2.59 ERA in 26 games (five starts) in the minors last season, split between Double-A Portland and Triple-A Worcester. He struck out 71 batters and walked 30 in 55 2/3 innings.
Garcia, an 18-year-old prospect from Mexico, was 2-4 with a 4.40 ERA in 11 starts in the Dominican Summer League in 2026.