Marlins prospect Deyvison De Los Santos to make MLB debut Sunday

Due to Christopher Morel going on the 10-day injured list, Deyvison De Los Santos will get his chance to live out his big league dream.

The slugging first base prospect was called up on Saturday and is expected to start in Sunday’s series finale against the Colorado Rockies. De Los Santos said the first thing he did upon receiving the promotion was to call his parents.

“They’ve all been waiting for this moment and I’ve been waiting for this moment as well since I was a little kid,” De Los Santos said through an interpreter. “Now I just need to do my best out there and just help the team win some games and stay out here.”

De Los Santos came to the Marlins in a 2024 midseason trade with the Arizona Diamondbacks for relief pitcher AJ Puk. In 2024, the 22-year-old hit 40 home runs and 120 RBI in the minor leagues. He struggled to replicate those numbers in 2025 but drove in 54 runs in 106 games in Triple-A Jacksonville.

He went 2-for-4 with a three-run homer in his lone game for the Jumbo Shrimp this season. De Los Santos said one of the things he has been working on for over a year in order to reach the big leagues was his emotions.

“To be a big leaguer, you’ve got to have that maturity, that mindset,” De Los Santos said. “That’s what it takes.”

Marlins manager Clayton McCullough said De Los Santos will likely see the bulk of his opportunities as a first baseman or designated hitter against left-handed pitching. He slashed .288/.326/.438 in 80 at-bats against lefties in Triple-A last year.

“Probably that’s where his opportunities starting will come from is versus left,” McCullough said.

Despite his young age, De Los Santos has already logged 206 games in Triple-A before getting called up.

“You forget how young he is,” McCullough said. “The power potential, the impact, we know that’s certainly something that we’re intrigued by acquiring De Los Santos, how hard he hits the ball, and him refining his at-bat quality, his approach offensively will probably be the determining factor of how much of that power he gets to in the Major League level.”

Morel was expected to start at first base for the Marlins on Opening Day, but strained his left oblique before first pitch. Morel, who signed a one-year $2M deal with the Marlins over the offseason, is expected to miss 4-6 weeks.

McCullough said they will have a better idea of how much time Morel will truly miss within the first two weeks.

“In the next week-10 days, we’ll have a better idea of what the range is but looking at somewhere around a month,” McCullough said.

Along with De Los Santos, McCullough said Connor Norby will get the majority of appearances at first base along with Liam Hicks when he’s not catching.