The old baseball adage—“you can never have enough pitching”—hit the Boston Red Sox harder than a 98 mph fastball in 2025. By season’s end, a dozen pitchers were sidelined on the injured list or battling health issues that rendered them unavailable. The crisis peaked in the winner-take-all Game 3 of the American League Wild Card series, where manager Alex Cora had no choice but to hand the ball to 23-year-old rookie Connolly Early for just his fifth big-league start.
Early battled valiantly, but a fourth-inning defensive meltdown and a dormant Red Sox offense sealed their fate. Cora would have much preferred veteran Lucas Giolito or rising arm Hunter Dobbins—both unavailable due to injury. The ordeal exposed Boston’s glaring lack of depth, prompting swift offseason action.
On Tuesday, the Red Sox moved to fortify their minor-league pitching pipeline by re-signing left-hander Eduardo Rivera, as reported by Boston Globe writer Alex Speier. Boston first acquired the flamethrower on June 12, 2024—mere weeks after his release by the Oakland Athletics and one day shy of his 21st birthday. A 2021 11th-round pick by Oakland out of Colegio Cadest High School in Carolina, Puerto Rico, Rivera now returns to the organization with intrigue and upside.
At 22 years old, Rivera is a towering 6-foot-7, 237-pound presence who dominated High-A and Double-A in 2025: a sparkling 2.48 ERA, 30% strikeout rate, and 13% walk rate. Speier notes he could emerge as mid- or late-season big-league depth in 2026. There’s a twist, however—Rivera is Rule 5 eligible this December. With five years of pro experience but no spot on a 40-man roster, any team could snag him for $100,000. The Rule 5 stipulation requires the drafting club to keep him on the 26-man active roster all season or offer him back, making him a risky but tantalizing target given his lack of Triple-A experience.
What makes Rivera a potential juggernaut? His fastball touches 98 mph and, per SoxProspects.com, is a “potential plus offering” that “jumps on hitters, especially left-handed hitters.” He maintains velocity deep into outings and even ramps it up in clutch spots.
Scouts aren’t blind to the rough edges: “Command and control need work. Below-average command profile. Pitches to the arm side frequently and has to work on being able to locate the pitch glove-side.” Refine those mechanics, and Boston might have unearthed a dominant lefty reliever—or more.
In a rotation starved for reliable arms, the Red Sox have bet on a Puerto Rican giant who could soon intimidate AL lineups. If Rivera sticks and refines his arsenal, 2026 might mark the arrival of Boston’s next homegrown fireballer.