The Boston Red Sox remained active right up until the trade deadline, and one of their biggest surprises came less than an hour before the cutoff.
According to The Athletic’s Ken Rosenthal, Boston is nearing a deal to send infielder Marcelo Mayer to the San Francisco Giants.
“Giants closer to acquiring Marcelo Mayer from Red Sox for reliever Erik Miller, sources tell me and Andrew Baggarly,” Rosenthal reported.
In return, the Red Sox are expected to acquire reliever Erik Miller. The move marks a significant shift for Boston, with Mayer-once regarded as one of the organization’s top prospects-reportedly on his way to San Francisco.
Mayer no longer fits
The trade represents a significant decision for Boston, which is parting ways with a young infielder who was once considered one of the organization’s brightest prospects shortly after his MLB debut.
Still only 23, Mayer has logged 332 major league at-bats, producing seven home runs, a .223 batting average, 74 hits, a 0.3 bWAR and a .625 OPS.
Although his numbers dipped this season before he was placed on the injured list-reflected in a 69 OPS+-the move remains an unexpected one given his age and pedigree.
Mayer is under team control through the 2031 season, but the deal suggests the Red Sox no longer view him as a central piece of their future.
With Caleb Durbin, Curtis Mead and a likely addition at shortstop expected to shape Boston’s infield, Mayer’s path to a regular role had become increasingly limited.
Why are the Red Sox trading Mayer for Miller?
Against that backdrop, the Red Sox ultimately chose to move him rather than keep him in a crowded infield picture.
Erik Miller arrives as an intriguing addition to Boston’s bullpen. The 28-year-old left-hander remains under team control through the 2029 season and has put together an impressive campaign, posting a 2.76 ERA, a 2-0 record, four saves and 45 strikeouts across 32.2 innings.
His ability to provide reliable left-handed relief should strengthen the Red Sox bullpen. Still, giving up Mayer-whose trade value may have been at its lowest-makes the deal a calculated gamble.
Red Sox eye postseason
At the same time, Boston may have concluded that waiting carried its own risks. Had Mayer returned from the injured list and continued to struggle, his value could have declined even further.
Ultimately, the move reflects the Red Sox’s focus on immediate contention. While Mayer’s long-term future in Boston had become uncertain because of a crowded infield, Miller has the potential to play an important role in the bullpen during a postseason push.