Back on May 2, the Boston Red Sox lost their first baseman to a serious knee injury. Triston Casas, Boston’s first-round draft pick in 2018, stumbled and fell while running out an infield ground ball and suffered a torn left patellar tendon, ending his 2025 season after just 29 games.
Casas played only 63 games in the 2024 season, with torn cartilage on his ribcage.
Red Sox in Market For Casas Replacement
Red Sox manager Alex Cora has been searching for a new first baseman ever since. Boston’s star designated hitter Rafael Devers flatly refused to take over at the position, essentially forcing a trade. The Red Sox shipped him to the San Francisco Giants where he quickly agreed to try his hand at first after all.
After the Devers debacle, the Red Sox turned to switch-hitting journeyman Abraham Toro, who caught on with the Red Sox this season after playing for four other teams in the previous six years.
But at the July 31 trade deadline, at least according to media reports, the Red Sox were targeting Josh Naylor, the seven-year veteran with 102 career home runs who despite making the American League All-Star team in 2024 was traded by the Cleveland Guardians to the Arizona Diamondbacks last December.
Naylor to Join Seattle Mariners
On Thursday, according to an MLB.com report, Naylor was traded again. But not to the Red Sox.
And that was not the only bad news for Cora, baseball operations chief Craig Breslow, and the Red Sox. Not only did they fail to acquire Naylor, but their closest competitor in the AL Wild Card race did.
Naylor, according to the report, was dealt from the Diamondbacks to the Seattle Mariners. The Red Sox and Mariners are currently in a virtual tie for the third and final AL Wild Card playoff berth. The Mariners are actually slightly in front with a .5294 winning percentage at 54-48. The Red Sox at 55-49 have a .5288 winning percentage.
Diamondbacks Receive Pair of Top Pitching Prospects
In return, the Diamonbacks will receive, according to MLB.com:
• Brandyn Garcia, a 25-year-old, 6-foot-4, 235-pound lefty currently pitching for the Triple-A Tacoma Rainers. Garcia comes with a feel-good story, working his way from a largely overlooked, 11th-round draft pick in 2023 out of Texas A&M, to become the Mariners No. 13 overall prospect just two years later — and the Seattle organization’s top-ranked left-handed pitching prospect (except for switch-pitching Jurrangelo Cijntje at No. 8).
• Ashton Izzi, a 21-year-old right-handed Single-A level who was Seattle’s fourth-round pick in 2022. The Mariners paid Izzi a $1.1 million signing bonus to lure him away from Wichita State, where he had committed to pitch in college.
As for Naylor, the 28-year-old Miami Marlins 2015 first-rounder avoided arbitration before this season by inking a $10.9 million, one-year pact with Arizona. That means the Mariners are likely picking up the Mississauga, Canada, native as a “rental” for the stretch drive as they attempt to secure one of the three Wild Card places.
Mets May Be Next Stop For Naylor
The New York Mets had also been linked to Naylor, not as much as a trade opportunity but as a free agent signing in the upcoming offseason if current first baseman Pete Alonso exercises the opt-out clause in his contract and goes back into the free agent market.
The Red Sox, on the other hand, will still be in the market for a first baseman with the trade deadline just one week away.
Red Sox Get Bad News on $10.9 Million All-Star Trade Target