Marcelo Mayer has been placed on the Red Sox’ 10-day injured list with a forearm bone stress reaction, a blow that also removes one of Boston’s top young prospects as the team navigates a season already strained by injuries.
When Marcelo Mayer walked into the season, he was supposed to be part of Boston’s future. By Friday night, he was headed to the injured list instead—another setback in a campaign the Red Sox have been trying to survive almost from the start.
The team placed Mayer on the 10-day IL with a forearm injury. with interim manager Chad Tracy saying the issue involves a bone stress reaction. The severity wasn’t described in detail. but the move came quickly enough that it landed Mayer on the IL on Friday night. Tracy also said Mayer has been dealing with it on and off “for a while.”.
The bone stress reaction matters because the description of the problem lines up with another player’s injury history. The Red Sox say Mayer’s forearm issue is similar to Isiah Kiner-Falefa’s.
For Boston, it’s not just one more injured player—it’s the loss of two top young prospects in close succession, right as the calendar gets tighter. Boston is already without its ace pitcher, Garrett Crochet, and now it will be without Mayer along with Roman Anthony for the near future.
In the immediate reshuffling, Tsung-Che Cheng will make his season debut at shortstop against the Yankees. The Red Sox are activating Cheng from Worcester, and he’s expected to play a lot of shortstop. Romy Gonzalez, meanwhile, is in Worcester at least one more day.
Mayer’s 2026 season has struggled offensively—he’s hitting .220 with 22 RBIs. and he’s only hit three home runs in 205 at-bats. Still, his presence has mattered defensively. He’s been a lineup staple at second base before transitioning back to shortstop, which is his Triple-A position. For Boston. that transition has carried weight because it helped cover the defensive hole created when Trevor Story went down with an injury.
But the Red Sox also haven’t escaped mistakes along the way. The article notes that Mayer has filled in for Story’s absence “save for a critical defensive error against the Rockies earlier in the week.”
Even with reinforcements beginning to return, the uncertainty is what hangs over Boston. Nate Eaton is back as a lineup option, and Romy Gonzalez is working through scheduled rehab. Yet the status of Story. Anthony. and Crochet remains unclear. and there’s been no news on Triston Casas’s injury either. Casas has missed large chunks of each of the last three seasons and has yet to make his 2026 debut.
The Red Sox’s problems are also affecting how they plan around the trade deadline. Mayer being the latest player to go down with an injury doesn’t help Boston’s chances of avoiding what’s been discussed as an all-out sell. The team is rumored to be shopping nearly all of its veterans, including future Hall of Fame closer Aroldis Chapman.
For Mayer personally, the injury may at least offer one chance the Red Sox haven’t been able to give him in a meaningful way: a reset. The report suggests the only possible silver lining is that it could allow him to regroup without being benched or demoted to Triple-A.
How long he’s out depends on what the forearm injury allows. If the issue isn’t serious. he could be eligible to return as soon as Boston’s series against the White Sox July 7-9. If the injury affects his ability to swing, it could take longer. The team has already seen how lingering forearm problems can stretch into weeks: Anthony has been out for nearly two months.
Boston’s next steps are already set—Cheng getting the start against the Yankees—and the emotional toll is familiar. Another promising piece, another abrupt detour. For a team already fighting through injuries. the timing of Mayer’s IL placement lands like another knock at the door just when the Red Sox most need stability.
Marcelo Mayer Red Sox 10-day IL forearm injury bone stress reaction Tsung-Che Cheng Roman Anthony Garrett Crochet Chad Tracy Yankees Worcester
IL already? man injuries never end with Boston.
Forearm bone stress reaction sounds like a fancy way of saying he’s hurt. 10 days turns into like a month anyways.
So they’re saying it’s similar to Isiah Kiner-Falefa’s injury history… does that mean Mayer shoulda never even played? Also .220 doesn’t help, but defense matters right?
Chad Tracy said it’s on and off for a while and now it’s “bone stress” like???? Meanwhile they’re calling up Tsung-Che Cheng to play shortstop against the Yankees, which feels like a setup for failure. I thought Roman Anthony was the guy everyone was watching too, so now it’s two prospects down right when they need everyone. Not sure why they didn’t just rest Mayer longer from the start instead of the quick IL move.