After Triston Casas suffered a season-ending injury in early May, the Red Sox have yet to locate a full-time first baseman, and their greatest chance to do so may not present itself until the conclusion of the season.
The New York Posts’ Jon Heyman believes the Red Sox are a serious contender to sign Mets star Pete Alonso, who is scheduled to become a free agent this winter.
Heyman claimed, “The Red Sox didn’t seem sold on Casas even before Tristan Casas was injured,” arguing that Alonso may move to Boston in the upcoming months. Even if they re-sign Alex Bregman, there is no assurance that they will be able to replace Rafael Devers’ bat. Alonso, who adores first base, is essentially a Devers clone offensively (his lifetime OPS is.859 compared to Devers’.856). His wife is from Boston.
Heyman made the argument that the Red Sox would accomplish multiple goals at once if they signed Alonso. Since joining the league in 2019, Alonso has been one of the best right-handed hitting sluggers, hitting at least 30 home runs in each season (apart from the COVID-shortened 2020 season), in addition to the clear need for a first baseman.
With 20 home runs in his first 90 games, Alonso is on track to have another 30-homer season in 2025. It’s important to note that the Red Sox haven’t had a hitter record that many home runs in a season since J.D. Martinez in 2019, even if Alonso is on pace to hit 36 home runs.
Alonso is having what may be his best season at the plate overall, even though he is also having another fantastic slugging season. His OPS of.929 would be the second-best of his career, and his batting average of.290 would be a career high. He leads the National League with 25 doubles, just six shy of his previous career high. In addition, he currently has 73 RBIs, putting him on track to reach a career-high 131 RBIs.
The Red Sox could definitely use a batter like that in their lineup right now. However, given that the Mets are trying to bounce back from their NLCS loss from the previous season, it is quite doubtful that they would want to part with Alonso. The Mets are in the midst of the National League pennant chase and are only a half-game behind the Phillies for the NL East lead going into Sunday.
However, Alonso might be reachable this offseason. Before spring training started, he accepted a two-year, $54 million contract to re-sign with the Mets because his market wasn’t that strong when he was a free agent last year. According to Spotrac, the Mets have already committed $228 million in payroll for the upcoming season (not including Alonso’s $24 million player option), after New York gave Juan Soto the biggest contract in MLB history during the offseason.
In the meanwhile, the Red Sox had some payroll flexibility after Devers was traded. According to Red Sox Payroll, their 2026 payroll commitments total about $197 million, which includes the options for Bregman, Trevor Story, Walker Buehler, and Lucas Giolito. The Red Sox would have just over $100 million committed in salary for the 2026 season if the options of all four players are rejected, which would leave them well below the $244 million first luxury tax level.
The Red Sox would also likely have long-term stability at first base if they signed Alonso. Heyman hinted that Casas was a trade candidate this past offseason as Boston looked for pitching help, despite the fact that he is only 25 and should recover from his ruptured patellar tendon in 2026.
But for the time being, the Red Sox will have to consider short-term solutions to cover the first base vacancy if they want to contend for the postseason. In the meanwhile, Romy Gonzalez and Abraham Toro have proved suitable substitutes.
However, Josh Naylor of Arizona and Ryan O. Hearn of Baltimore would probably be the two best choices if Boston wishes to lock down first base before the trade deadline. In his first season with the Diamondbacks, 28-year-old Naylor is hitting.302 with 10 home runs and a.822 OPS, while O Hearn, 31, is hitting.289 with 11 home runs and a.841 OPS. At the end of the season, both players will be eligible for free agency.
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