Marlins To Add Three Players To 40-Man Roster

The Marlins are going to be selecting three players to their 40-man roster ahead of today’s Rule 5 protection deadline, reports Christina De Nicola of MLB.com on X. They are infielders Deyvison De Los Santos and Jared Serna as well as left-hander Dax Fulton. The 40-man roster will be full when the moves are official.

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.