Marcelo Mayer fell to the Boston Red Sox, who selected him with the No. 4 overall pick in the 2021 MLB draft. Since then, he has steadily climbed through the organization’s minor league system while consistently ranking among baseball's top prospects. Before earning his first big-league promotion last season, Mayer hit .271 with nine home runs and a league-leading 43 RBI for Triple-A Worcester. In a limited MLB action, Mayer flashed his All-Star potential, hitting four home runs and driving in 10 runs.
When available, Mayer has looked like a cornerstone piece. He’s shown advanced plate discipline for his age, a compact left-handed swing built for Fenway Park, and the ability to drive the ball to all fields.
Defensively, Mayer’s versatility has only strengthened his case to remain in Boston’s long-term plans. While originally developed as a shortstop, his arm strength, instincts, and range project well to third base, where the Red Sox could benefit from his athleticism on the left side of the infield.
However, injuries have been the biggest obstacle in Mayer’s young career. His 2023 season was cut short by a shoulder injury, and his 2024 season ended because of a lumbar strain. Last season, Mayer’s season followed a similar pattern as he underwent wrist surgery in August, once again bringing his year to an early close.
With the departure of Alex Bregman in free agency, Mayer currently projects as the favorite to take over as Boston’s starting third baseman. Still, the 23-year-old will need to prove that he can stay healthy over a full season. If Chief Baseball Officer Craig Breslow doesn’t believe in Mayer’s ability to stay healthy, the team is already rumored to be interested in free agent third baseman Eugenio Suarez or trading for Houston Astros third baseman Isaac Paredes.
The 2026 season represents more than just another step in Mayer’s progression; it may ultimately determine his long-term future in Boston. A healthy, productive year could cement him as the Red Sox’s long-term answer at third base and a key piece of their youth movement. Conversely, another injury-shortened season could push Boston toward external solutions and potentially move Mayer into trade discussions.
In that sense, Mayer enters 2026 not just with expectations, but with real pressure, making it a defining year that could shape both his career trajectory and the Red Sox’s plans moving forward.