Miami Marlins first baseman Jesus Aguilar Bill Streicher-USA TODAY Sports

Marlins first baseman Jesus Aguilar has been on the injured list for the past week with inflammation in his left knee, and he’s “highly unlikely” to return to the active roster in 2021, per Craig Mish and Barry Jackson of the Miami Herald. He’s received multiple opinions on the knee as the team looks to determine how to treat the injury.

It’s been a productive 2021 campaign at the plate for the 31-year-old Aguilar — his second straight season of quality output after being claimed off waivers from the Brewers organization in Dec. 2019. Between last year’s truncated schedule and this year’s injury-marred finish, Aguilar has appeared in a bit more than a full season’s worth of games as a Marlin, batting a combined .265/.336/.458 with 30 home runs and 33 doubles in 726 plate appearances.

Given last year’s modest $2.575M salary and this year’s $4.35M mark, he’s been a bargain for the Fish. As is always the case with Marlins players entering their final arbitration season, there’s at least some degree of uncertainty regarding Aguilar’s future with the club. His 22 homers and 93 runs batted in this season will help to fuel another boost on that $4.35M salary in arbitration, and while his forthcoming raise wouldn’t be exorbitant, it could push into the $6M-7M range. For some loose context, Nick Castellanos hit 23 home runs and plated 89 runs heading into his final arbitration raise and got bumped from $6.05M to $9.95M — a 64.4% raise. A raise of similar magnitude would push Aguilar just north of $7M, but it’s worth pointing out that Castellanos had better rate stats, more games and more plate appearances in his platform season.

Prospect Lewin Diaz has been getting a look in Aguilar’s absence, and his performance could also inform Miami’s eventual decision. While Diaz had a dreadful run earlier this season with the Marlins, he swatted two homers Tuesday night and has batted .280/.280/.680 in a tiny sample of 25 plate appearances since being plugged into the everyday lineup. The 24-year-old Diaz isn’t necessarily an elite prospect, but he’s posted a .248/.327/.518 batting line with 20 homers in 74 games and 314 plate appearances with Triple-A Jacksonville this season.

The advent of the universal designated hitter, if it indeed comes to fruition as many expect this winter, could make it easier for the Marlins to retain Aguilar. That’d allow both first basemen to receive regular looks in the lineup, giving Diaz a potentially extended runway to prove himself as a big leaguer without sacrificing the production provided by the steady veteran Aguilar.

The Marlins have all but said they’ll exercise their $5.5M option on shortstop Miguel Rojas at season’s end, and the only other commitments on their 2022 books are the $3M they owe to the Yankees as part of the Giancarlo Stanton trade and Anthony Bass’ $3M salary. They’ll have some other raises to consider, most notably Brian Anderson (arb-eligible for a raise on his $3.8M salary) and first-time arb players like Sandy Alcantara, Pablo Lopez and Elieser Hernandez.

Mish reported near the trade deadline that the Marlins had interest in signing Aguilar to an extension, but only through the 2023 season (Twitter link). Perhaps that’d intrigue Aguilar more now, given the recent injury and the broader manner in which the market has come to devalue defensively limited first basemen on the wrong side of 30. On the other hand, Aguilar is only a year from the open market and could theoretically benefit from the potential addition of a DH in the National League, so delaying free agency for just one guaranteed year (at what would presumably be a club-friendly rate) may not hold much appeal. Of course, the eventual diagnosis and prescribed treatment will be critical for both the player and the team as pertains to Agular’s future in Miami.

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