Red Sox interested in exploring long-term extensions with top prospects

At yesterday’s Fenway Fest fan event, Red Sox top prospects Roman Anthony and Kristian Campbell indicated that they have not heard from the club’s brass regarding the possibility of signing long-term extensions in Boston to this point. Today, a report from Alex Speier of the Boston Globe relays that while the Red Sox have not yet reached out to begin extension discussions, the team is nonetheless interested in exploring the possibility with its top prospects.

Namely, Speier lists Anthony, Campbell, and top infield prospect Marcelo Mayer all as youngsters the club is hoping to talk extension with. Campbell, in particular, has made clear that he would be interested in negotiating if the Red Sox approach him. Speier notes that the club’s 2023 fourth-rounder told reporters last season that he would be “100 percent” open to a long-term deal with Boston and also reports that Anthony is seen as being willing to “at least listen” if the Red Sox were to approach him about signing a long-term extension.

All three youngsters come with significant prospect pedigree. According to Baseball America, Anthony is the top prospect in all of baseball, while Mayer sits just behind him at #10 and Campbell clocks in at #24. MLB Pipeline, meanwhile, has all three youngsters within the top ten: Anthony is ranked #3 overall behind Dylan Crews of the Nationals and Walker Jenkins of the Twins, while Mayer comes in at #7 and Campbell rounds out the trio at #10. The trio’s performance on the field has generally backed up those rankings, as well. Campbell flew through three levels of the minors in 2024, slashing .330/.439/.558 along the way, while Anthony hit .291/.396/.498 at the Double- and Triple-A levels last year. Mayer was limited to just 77 games at Double-A due to injuries last year but nonetheless hit a solid .307/.370/.480 at the level in his age-21 season.

Pre-debut extensions for players with that level of prospect pedigree are somewhat rare but one did occur last winter between the Brewers and outfielder Jackson Chourio, who had been ranked as the #2 prospect in baseball by both Baseball America and MLB Pipeline at the time of the deal. Chourio wound up signing an eight-year extension last offseason that guaranteed him $82MM with club options and incentives that could allow the deal to max out at $142.5MM over ten years. Chourio’s extension seems like it would be a sensible benchmark for Anthony should he wind up signing a deal before making his big league debut, given their similar prospect rankings and Anthony’s status as a similar five-tool outfielder who projects to land in a corner at the big league level.

Campbell and Mayer, on the other hand, may not be in line for paydays at quite that level. Tigers infielder Colt Keith landed at the other end of the pre-arbitration extension spectrum when he signed a six-year deal last winter. That contract guarantees Keith just $28.6425MM and maxes out at $82MM over nine years if the Tigers pick up a trio of club options they hold on the youngster’s services. Prior to the 2024 season, Keith was ranked as a consensus top-30 prospect in the game but did not crack the top 20 with any major service. That limits Keith’s usefulness as a point of comparison for Campbell and Mayer, given both are rated as top-10 prospects by at least one major prospect outlet.

Keith also falls lower on the defensive spectrum than Campbell and especially Mayer. He was limited to second and third base throughout his time in the minor leagues while both Red Sox infielders have spent much of their time in the minors at shortstop. While Campbell has mixed in work at second base and in the outfield and manager Alex Cora suggested to reporters (including Christopher Smith of MassLive) yesterday that the club plans to have Mayer start playing second and third base in addition to shortstop this year, the ability to play shortstop along with stronger prospect pedigree seems likely to allow both Red Sox infielders to set their asking prices meaningfully higher than Keith’s deal.

Of course, it’s also possible the Red Sox could wait to work out an extension with one or more of the trio until they’ve already debuted in the majors. Speier notes that the club extended utility man Ceddanne Rafaela back in April on an eight-year, $50MM deal just over 100 plate appearances into his big league career. That deal can max out at $62MM over nine years, but it’s on the low end of deals signed at that stage in a player’s career in recent years; only Aaron Ashby’s $20.5MM extension with the Brewers guaranteeing less in the past half decade. A look at MLBTR’s Contract Tracker demonstrates how quickly a player’s asking price can skyrocket once they’ve accrued big league service time. Julio Rodriguez’s $210MM guarantee with the Mariners is the most lucrative deal of the bunch, though Wander Franco, Corbin Carroll, and Ronald Acuña Jr. are among the other extensions signed with less than a year of big league service time that eclipsed the $82MM guarantee Chourio secured from the Brewers last offseason.

Given how quickly the price of an extension can rapidly escalate once a young star begins to establish themselves at the big league level, it’s easy to imagine the Red Sox being particularly motivated to see if a deal between the sides can be reached in the coming months. With that being said, the club has shown a willingness to extend players later into their career as well. Boston brass are already known to have begun discussions with left-hander Garrett Crochet about a possible extension with two years left before free agency, and the club has previously extended Xander Bogaerts and Rafael Devers on nine-figure deals ahead of their final seasons before free agency.