De Los Santos, 22 in June, just arrived with the Marlins at the trade deadline. He was one of two young players that the Fish received when trading lefty A.J. Puk to the Snakes in July. He went on to hit .240/.284/.459 while striking out in 28.4% of his plate appearances after the deal, leading to an 85 wRC+.

The Marlins are undoubtedly hoping that he can get back to the form he showed prior to the trade. In 87 contests this year ahead to the deal, he produced a robust .325/.376/.635 slash line while launching 28 home runs, leading to a 159 wRC+.

De Los Santos is a divisive prospect because the power is exciting but most of his other tools are considered weak. He has played both infield corners but isn’t well regarded for his glovework. He doesn’t take walks or provide much on the basepaths.

Still, a rebuilding club like the Marlins could give him some at-bats and see if the homers make him valuable regardless. The Fish have guys like Jake Burger, Jonah Bride and Connor Norby in their corner infield rotation but De Los Santos will give them some depth there. He already had 99 games of Triple-A experience and could make his major league debut at any time.

Serna, 23 in June, is also a new Marlin. He was one of three players to come from the Yankees as part of the Jazz Chisholm Jr. trade from this summer. He has slashed .265/.358/.435 over his four minor league seasons, walking at a solid 10.8% clip while keeping his strikeouts down to a 16.6% level, production leads to a 123 wRC+.

He may be ticketed for a utility role down the line, as he has played shortstop, second base, third base and a bit of right field as well. His shortstop defense isn’t considered especially strong, so he may end up playing those other positions a bit more. Prior to the trade, he had never played above High-A, so a major league debut might not be imminent. The Marlins did put him into 39 Double-A games and 6 Triple-A games after the swap, but he’s probably ticketed for more time in the upper levels of the minors next year.

Fulton, 23, is unlike the other two in that he was actually drafted and developed by the Marlins. A second-round pick from 2020, he has posted some strong numbers but hasn’t pitched since undergoing surgery on his ulnar collateral ligament in June of 2023. Prior to that surgery, he posted a 4.27 ERA in 229 2/3 innings across multiple levels from 2021 to 2023. His 10% walk rate was a bit high but he punched out 27.6% of batters faced. He will presumably need some time to get back into game shape after missing all of 2024, but he will eventually provide the Marlins with some pitching depth when he is back to full strength.

Fulton becomes the latest in a deep crop of Marlins pitching prospects to incur a major injury setback, although given the sheer volume of quality pitching in Miami’s system and the general attrition rate of pitching prospects, injuries throughout the group were inevitable. Sixto Sanchez has had multiple shoulder surgeries, while Max Meyer and Jake Eder both underwent Tommy John surgery last year.

Fulton isn’t necessarily as touted as that trio, though Keith Law of The Athletic ranked him among the game’s top 100 prospects heading into the season. The former No. 40 overall draft pick pitched to a combined 3.80 ERA in 118 1/3 frames between High-A and Double-A in 2022 and opened the 2023 season back at Double-A. With a strong showing in Pensacola, a promotion to Triple-A was likely — and an eventual 2023 look in the big leagues likely wasn’t entirely off the table.

Fulton already had Tommy John surgery in high school. A second surgery to address the ulnar collateral ligament in his left elbow before he’s even turned 22 years old is an ominous development, but the Marlins are currently hopeful that he’ll be ready for spring training 2024, per the Herald report.

The Marlins placed Fulton on the minor league injured list last month. Prior to landing on the shelf, he’d made six starts and a relief appearance in Double-A Pensacola, pitching to a 5.18 ERA with a 26.4% strikeout rate against a rough 12.8% walk rate. Scouting reports on Fulton tout his plus breaking ball, and Law credits him with a plus changeup as well. Fulton isn’t a flamethrower by today’s standards, topping out at 96-97 mph with his heater and averaging a few ticks shy of that max output.

If Fulton is indeed back to full strength next spring, he could still reach Triple-A next year and be on the doorstep of the big leagues, though with just 33 innings pitched this year, his workload will figure to be monitored. He’s not yet on the 40-man roster and won’t be eligible for selection in the Rule 5 Draft until the 2024-25 offseason, so the Marlins don’t yet need to worry about exhausting his minor league options. The focus for now will be on getting the promising lefty back to full strength and ready for the ’24 campaign.

It seems that strategy is still in play, with Barry Jackson and Craig Mish of the Miami Herald reporting that the club will again look to swap some pitching for some more offense. The report lists ace Sandy Alcantara and the club’s top prospect Eury Perez as the two “untouchable” arms on the team, with the others apparently available for the right price.

In addition to the Thompson trade, there were a few other ways in which the club’s rotation surplus was reduced in the past year. Prospect Max Meyer made two starts before Tommy John surgery put him out of action for the rest of this year and potentially all of next year as well. Sixto Sanchez has continued to deal with shoulder issues, not having thrown in a game since 2020. Elieser Hernandez struggled enough that he got bumped to the bullpen and later optioned to the minors.

Those setbacks aside, the club still has a mix that includes Alcantara, Pablo Lopez, Edward Cabrera, Jesus Luzardo, Trevor Rogers, Braxton Garrett, Daniel Castano, Nick Neidert, with the report listing Lopez, Cabrera and Rogers as logical trade candidates. It also says the club would consider dealing prospects to a rebuilding team in order to get MLB-ready players. Though Perez is apparently not on the table, Jake Eder and Dax Fulton are mentioned as possibilities.

Lopez, 26, is no stranger to trade rumors, having been frequently mentioned both as someone who could be moved and as someone garnering interest around the league. It was reported last week that the Marlins and Yankees had discussed a deal prior to the deadline that would have seen the Fish acquire Gleyber Torres and infield prospect Oswald Peraza, though the Yanks apparently balked at the deal. There’s no real hurry for the Marlins to deal him, as he can be controlled through the 2024 season via arbitration. He’s in his third straight strong season, registering a 3.66 ERA through 25 starts this year. Perhaps most importantly, he has stayed healthy and put aside some concerns after he missed some of last year with shoulder issues. He’s making $2.45MM this year and will get a raise for next season via arbitration, though he will still be plenty affordable and should find lots of interest from other teams.

The 24-year-old Cabrera would make for a very different trade chip, having much more control but less of a proven track record. He just made his MLB debut last year and missed about six weeks this season due to elbow tendinitis. He only has 15 MLB starts on his ledger so far but has shown promise in that time, registering a 3.71 ERA in his young career. He came into this year with just 40 days of MLB service time but was optioned in the spring and didn’t get recalled until June 1, which should lead to him coming just shy of the one-year mark at the end of this season, even if he remains in the big leagues for the rest of the campaign. That means he should still have six years of control beyond this one, though he is in his final option year, which will mean he will need to hold a spot on an MLB roster starting next year or else be designated for assignment.

Rogers, 24, broke out last year with a 2.64 ERA over 25 starts but has regressed here in 2022. He has a 5.85 ERA through 19 starts and has been on the IL for over a month due to back spasms. He should still hold appeal given his previous showing and four remaining years of control, but he’ll certainly have diminished trade value compared to a year ago.

Eder, 23, was a fourth-round draft pick in 2020. The lefty made 15 Double-A starts last year with a 1.77 ERA before undergoing Tommy John surgery in August. He’s out for this year and might be limited in 2023, though the Marlins are hoping to deal him to a rebuilding club, who may not be so concerned about the short-term outlook. Fulton is also a left-hander but much younger, turning 21 in a couple of months. He was a second round pick in 2020, having since climbed up to Double-A. Between High-A and Double-A this year, he has a 4.05 ERA across 102 1/3 innings.

Whether the club can work out a deal with will of course depend upon lining up with another club. A team with designs on immediate contention would likely be more interested in Cabrera, Rogers or Lopez, while a rebuilding club would lean towards Eder and/or Fulton. It will also depend on what that theoretical other club has to offer the Marlins in return. As Jackson and Mish note in their report, the Marlins will be using the final weeks of the season to audition certain position players and evaluate their future roles. JJ Bleday, Lewin Diaz, Jerar Encarnacion and Peyton Burdick are all listed as players trying to secure jobs on the 2023 team. How they fare in those auditions could have an impact on who the Marlins look to target in trades to improve their lineup. The team as a whole has been about 12% below league average at the plate this year, as indicated by their 88 wRC+, a mark that places them 26th in the majors.