JUPITER—The Miami Marlins believe Adam Mazur can be a long-term starter, but he made just six appearances for the big league club in 2025, posting a 4.80 ERA. Unsatisfied with those mixed results, the right-hander focused this offseason on adding good weight to his tall, lengthy frame.
Following his start on Monday afternoon, Mazur said he added 15–20 pounds of muscle over the offseason thanks to consistent work in the gym and 1,000-calorie protein shakes every morning, along with regular meals throughout the day. “Hopefully that’ll help me stay healthy throughout the year.”
Although Mazur faces an uphill battle to crack the Marlins Opening Day roster, the fact that he already occupies a 40-man roster spot could get him up to Miami relatively early in the season. It’s a similar situation for Joe Mack, who was behind the plate for Mazur’s two hitless frames against the St. Louis Cardinals.
“Love him. Getting time with him last year in Jacksonville was great. He’s a great catcher, great guy, and I love spending time with him,” Mazur added. “He reads pitchers well. If he knows a guy is missing on one side or the other, he can set up differently. He’s got a great feel for the team and a rocket of an arm back there, so it’s always nice to have.”
Mack raved about Mazur postgame, telling reporters that “he looked really, really good today. You can tell he put in a lot of work in the offseason, especially in pitch design.”
After being charged with a catcher’s interference in the first inning, Mack made up for it with a stellar pickoff in the second, firing an 87.1 mph dart to first base from his knees.
“We try to work on back picks at least once or twice a game, and we noticed they were being a little lazy getting back to the bag. I was given a sign and made the throw,” he said.
With catcher Liam Hicks (Canada) and Agustín Ramírez (Dominican Republic) away representing their respective countries in the World Baseball Classic, Mack will have an opportunity to show he’s ready for the next step.
“Having that runway of playing time will be huge for him,” Marlins manager Clayton McCullough said postgame. “He was in big league camp a bit last year, and with him getting to Triple-A last season, he’ll be a guy everyone should certainly watch.”
While Ramírez and Hicks are projected to be the tandem on Opening Day, Mack is expected to be an early call-up, providing continuity and strong defense behind the plate in 2026 and beyond.
News and notes
– Josh Ekness, the 27th-ranked prospect according to Fish On First, turned in his best outing of the spring, tossing a perfect inning with two strikeouts. He topped out at 98 mph.
– Free-agent addition John King recorded his third scoreless outing of the spring and is expected to serve as Miami’s highest-leverage left-handed reliever.
– Prospects Josh White and Nigel Belgrave struggled, combining to allow all three runs scored by St. Louis. Belgrave surrendered the walk-off hit in the ninth after yielding a hit and hitting a batter.
– Top prospects Dillon Lewis and Kemp Alderman each squared the ball up twice Monday, with Alderman launching his first home run of the spring. The power-hitting reigning Marlins Minor League Player of the Year is expected to debut sometime in 2026.
– The Marlins will face Team Israel on Tuesday afternoon, with Braxton Garrett scheduled to start.