Red Sox promote top prospect Marcelo Mayer after 'significant' Alex Bregman injury
The Boston Red Sox promoted top infield prospect Marcelo Mayer and are placing third baseman Alex Bregman on the injured list with a "significant" quad injury.
Bregman left May 23's game at Fenway Park against the Baltimore Orioles, coming up limping as he turned first base after a hit.
"He's going to be out for a while," manager Alex Cora told reporters a day after Bregman's injury.
Mayer, the fourth overall pick in 2021, has 43 RBIs in 43 games for Class AAA Worcester this season. The 22-year-old was drafted as a shortstop and played almost exclusively there in his five minor-league seasons, but has gotten reps some at second and third in 2025.
"We'll play him everywhere," Cora said of Mayer.
A left-handed hitter, Mayer is big for a shortstop at 6-foot-3 and has struggled at times against lefties in the minors (.674 OPS in 2024), but his power profiles well and has a strong arm that will be useful at any infield position.
Boston's infield is something of a puzzle this year, with the winter addition of Bregman pushing Rafael Devers off the hot corner to designated hitter. Rookie Kristian Campbell began the season at second base and Trevor Story has been the shortstop, but the veteran has a .607 OPS through 49 games. First baseman Triston Casas suffered a season-ending injury earlier in May, and Devers declined the team's request to give the position a shot – leading to Boston preparing Campbell to play first.
With Campbell established in Boston and Mayer joining the group, next up in the pipeline for the Red Sox is outfielder Roman Anthony, currently ranked as baseball's No. 1 overall prospect by MLB.com. The 21-year-old is hitting .323 with a .968 OPS and should reach the majors this season.
"About time," Anthony posted on Instagram as news of Mayer's promotion spread. "Go be you brother."
Marcelo Mayer stats
Marcelo Mayer is hitting .271 with nine home runs and 43 RBIs in 43 games for Class AAA Worcester. In 2024, Mayer hit .307 with an .850 OPS at Class AA Portland.
Marcelo Mayer prospect rankings
(Pre-2025 season rankings)
- Baseball America: No. 15 overall
- Major League Baseball: No. 12
- Baseball Prospectus: No. 25