The Marlins selected Serna's contract from Triple-A Jacksonville on Tuesday, Christina De Nicola of MLB.com reports.
Serna was dealt from the Yankees to the Marlins in the Jazz Chisholm trade and has now joined Miami's 40-man roster. The 22-year-old began the 2024 season at the Low-A level before finishing it at Jacksonville, slashing .251/.337/.414 with 15 homers and 15 steals over three stops. He mostly played shortstop last season but can also handle second and third base.