How Red Sox’s Marcelo Mayer Can Reintroduce Star-Level Potential In 2025

Before the start of the 2025 season, NESN.com is evaluating several noteworthy prospects in the Boston Red Sox organization, using insight and analysis from industry experts to gauge each player’s outlook for the upcoming campaign. Next up: Marcelo Mayer.

The Red Sox have built a tremendous farm system that’s undergone a major reconstruction since 2020.

Boston took Nick Yorke in the first round of the 2020 MLB Draft, though the top-tier rebuild truly began with the selection of California high school infielder Marcelo Mayer at No. 4 overall in 2021.

Impact prospects such as Roman Anthony and Kristian Campbell since joined him at the top of rankings, but Mayer always sat at the center. Mayer’s talent and leadership qualities have stayed consistent despite injuries. So, optimism for Mayer should still be very high heading into 2025.

Background
Mayer rose as a superb talent at Eastlake High School in Chula Vista, Calif. And he entered the system with major expectations on and off the field, starting with his value as a teammate and a leader for the Red Sox’s future.

“I do think he brings a lot to the clubhouse in the sense that he’s bilingual,” Ian Cundall, director of scouting for SoxProspects.com, told NESN.com. “He’s able to communicate with pretty much everybody on the team. I think that’s a pretty big role. He kind of sets the tone in that regard.”

Mayer gave interviews over the years with dreams of duck boats and championship parades in the next wave of Red Sox greatness.

He rose through the minor leagues with solid production in somewhat limited time on the field due to injuries in 2022, 2023 and 2024. He reached Triple-A Worcester in 2024 and now sits one step away from his MLB debut with Boston.

Scouting Report
Mayer has a strong build at shortstop, with quality movements and the physical traits to play the position. At the plate, his power from the left side is evident despite a smaller-than-anticipated sample size.

“The power really took a big jump last year,” Baseball America’s Geoff Pontes told NESN.com. “He’s always had a natural bat-to-ball ability. Pretty left-handed swing as a line-drive hitter.”

Pontes pointed to two-time World Series champion and former Red Sox shortstop Xander Bogaerts as a potential comparison that Mayer can grow into from a production standpoint.

“He’s been remarkably consistent,” Cundall said. “He’s hit for power. He’s hit for average. He’s had a high OBP throughout his career. The biggest thing with him is he’s just got to be healthy.”

That was, is and will be the deciding factor on Mayer’s future. He’s yet to play 100 games in a season during his three full years in the Red Sox system. Nobody doubts the player and his potential, but Mayer needs to reaffirm the Red Sox’s belief in him.

“The consistent thing is when he’s on the field, the talent is extraordinary,” Red Sox senior director of player development Brian Abraham told NESN.com. “The work that he’s put in, the weight that he’s put on. The improvements on the offensive side and the defensive side are really exciting to see. We’re looking at an up-the-middle player, a top- or middle-of-the-order bat that really leads by example. Players tend to gravitate towards him.” 

Most-likely outcome: Versatile infielder.

Mayer’s frame ultimately could take him to third base or second base, but that’s not a knock on his ability to play shortstop. His bat is enough for any team to find him a spot. Where that is depends on a number of factors on the Red Sox roster.

Best-case scenario: All-Star.

Mayer’s defense, impact bat and leadership qualities make up the profile of an MLB All-Star who can top out with strong production for a decade-plus.

Players such as Nomar Garciaparra and Bogaerts became franchise mainstays at shortstop. Mayer’s potential could put him in that conversation one day.

Fenway forecast
Mayer’s injuries have him behind Anthony and Campbell on the path to his MLB debut. Mayer got a call-up to Triple-A last season but never took the field. He needs sustained time there to prove his durability to the Red Sox, so barring injuries at the MLB level, don’t expect to see Mayer until after the 2025 All-Star break.

“Timeline-wise, you’re probably looking at the summer,” Cundall said. “He’s still never played in Triple-A. It’s the totality of the at-bats he’s missed in his career because he’s been injured.”

The Red Sox even could push Mayer’s debut to 2026 — for a full year at Triple-A — and assess his roster fit based on opt-out decisions for Alex Bregman and Trevor Story.

SoxProspects.com ranking: No. 3
Mayer likely will stay in this spot unless Anthony and Campbell graduate far enough ahead of him, at which point he could jump to No. 1.