No. 9 prospect Mack making way at Double-A

This story was excerpted from Christina De Nicola’s Marlins Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

It would’ve been easy for Marlins No. 9 prospect Joe Mack to express his disappointment at beginning his 2025 campaign at Double-A Pensacola -- the same level he dominated in ’24.

Mack broke out last season, slashing .241/.322/.456 with 25 doubles, 22 homers and 65 RBIs in 112 games for the Blue Wahoos en route to Double-A MVP honors. He also captured a Minor League Gold Glove Award for defensive excellence at catcher.

“I'm happy to play baseball wherever I am, even if they sent me to [Single-A] or wherever,” Mack said. “It wouldn't matter. It's baseball, and I'm excited to play wherever I'm at: big leagues, Minor Leagues, wherever. I'm just trying to play the game, have a fun time and do as best as I can.”

The reason why Mack returned to the Double-A level is a simple one: Marlins No. 4 prospect Agustín Ramírez is at Triple-A Jacksonville. Ramírez is ahead of Mack in his professional career, and the organization would like them both to get full reps in order to aid in their development.

“Obviously, Mack right behind him -- shouldn't say 'behind' him -- but just somebody who's also obviously very impressive and continues to just wow us with his capabilities behind the plate and his arm,” said director of player development Rachel Balkovec.

After injury-riddled seasons to open his pro career, Mack slashed just .218/.295/.287 with 13 doubles and six homers in 120 games at High-A Beloit in 2023. With plenty to prove in ‘24, Mack took off and earned a promotion to the Blue Wahoos after just 13 contests with the Sky Carp.

A year later, Mack is in a different head space despite the familiar surroundings.

“I believe I improved on both sides of the plate, hitting and catching,” Mack said. “I've been working a lot on my receiving, my blocking and my throwing. All that stuff has not stopped since the offseason, and my hitting has just improved off of last year. I didn't change anything. I didn't go in and try and tweak everything. We just kept it the same and just upped the work and made it more challenging. Able to kind of dig within myself and understand my own limits.”

For his efforts, the 22-year-old Mack received his first big league camp invitation and more than held his own in Grapefruit League play, going 6-for-17 (.353) with one double, two walks, two RBIs, three runs and three strikeouts.

More importantly, Mack learned from veteran catcher Rob Brantly about life in baseball and the importance of a daily routine – from nutrition to hydration to game prep. When Miami reassigned Mack to Minor League camp, the feedback was positive.

“Joe has a chance to be a special player at that position, on both sides of the ball,” Marlins manager Clayton McCullough said. “Left-handed with some power, but there's some real hit ability, too, in Joe. And then on the defensive side, he can really throw. He's handled himself well, catching a lot of our Major League arms. So [I] hope this has been a great experience.”

Even with the success Mack experienced in 2024, there is room for improvement. The left-handed hitter must fare better against southpaws (.688 vs. .841 OPS and just eight of his 54 extra-base hits entering Tuesday). Mack also needs to manage the game behind the plate; one of his main duties is to work with some of the organization’s top arms like Robby Snelling (No. 8 prospect) and Dax Fulton (No. 14).

None of this is possible unless Mack stays healthy, which is once again his primary goal. Then there’s making every at-bat his best one, trusting the process over the result.

So far, so good. Mack was named the Southern League Player of the Week on Monday by hitting .438 with two homers, four RBIs and six runs.

“He's a very good catcher,” Fulton said. “I have nothing but good things to say about Joe. Honestly, he works his tail off. But he's just a good person as well. He's one of those guys that you really wish him to be successful. He's a good clubhouse guy. He's a good leader. He leads by example as well, and he's just one of those guys that you really root for in general, and he works really hard for us behind the plate.”