Why Adam Mazur could be next man up for Marlins following Luzardo trade

Starting rotation depth was supposed to be a strength of the Miami Marlins entering last season, but that wasn't exactly the case. Injuries forced the team to make constant changes and the results were mediocre. In 2025, they may have to once again rely on inexperienced starters, especially following Sunday's trade that sent left-handed pitcher Jesús Luzardo to the Philadelphia Phillies in exchange for two prospects.

Following the trade, the projected rotation includes Sandy Alcantara, Edward Cabrera, Ryan Weathers and Braxton Garrett. With Eury Pérez rehabbing from the Tommy John surgery, the question is who will earn the fifth spot on Opening Day.

Valente Bellozo made 13 starts as a rookie, which ranked fifth on the Marlins behind Cabrera, Weathers and two pitchers who are no longer with the organization, Trevor Rogers and Roddery Muñoz. The soft-tossing right-hander was a big success story with a 3.67 ERA, but his 5.73 FIP suggests he's very unlikely to sustain that moving forward.

Former first-round draft pick Max Meyer made 11 total starts. He was demoted to Triple-A Jacksonville despite an April hot streak and slumped during the second half to finish with a 5.68 ERA.

However, in addressing the media on Sunday, president of baseball operations Peter Bendix mentioned two other names instead when discussing Miami's rotation: Adam Mazur and Robby Snelling. "We have a lot of depth there as well as a lot of high-end talent, so I'm really excited to see how it shakes out," said Bendix.

Mazur, 23, was one of four players acquired from the San Diego Padres in exchange for Tanner Scott and Bryan Hoeing. He has already seen time at the major league level, but the Padres rushed his development and the poor numbers reflected that (7.49 ERA, 6.23 FIP, 5.88 K/9 and 5.61 BB/9).

Following the trade, the Marlins assigned Mazur to AAA-Jacksonville. In eight starts, he posted a 5.21 ERA, 4.67 FIP, 9.00 K/9 and 1.66 BB/9. He looked more like his usual self in terms of good control, limiting opponents to zero walks in five of those starts.

Along with a high walk rate, Mazur struggled against MLB hitters because his fastball and curveball were getting crushed. The fastball, which averages 95.0 mph, was taken deep four times. He allowed a .333 batting average on it and an average exit velo of 93.5 mph with only a 13.4 whiff%. In a smaller sample, the curveball failed even more (.364 batting average, 93.9 mph exit velo and 8.3 whiff%).

It was encouraging to see Mazur's swing-and-miss improvement on both pitches during his Jumbo Shrimp stint. He added a little velocity and horizontal break to the curveball on his way to a 32.4 whiff%. His fastball velo remained the same as its whiff% went up to 19.1%. 

Mazur's slider is his signature pitch. The key is having enough trust in the rest of his arsenal to put him in strikeout situations, and he looks to be on the right track. Our own Isaac Azout will be following his progress closely after predicting him to make the Opening Day roster on the latest episode of Fish Unfiltered.

Snelling, 21, reached the AAA level at the very end of the 2024 season after a great showing in AA-Pensacola. Snelling's velocity was down compared to his 2023 breakout year, but the command of all his pitches was impressive after joining his new organization.

Snelling is a safe bet to attend big league camp, but it's a long shot that he starts the regular season in Miami given his lack of a 40-man roster spot and limited AAA experience.

Several other pitchers who are already on the 40-man could be stretched out as starters during spring training. Meyer was excellent last spring and is capable of bouncing back. Xzavion Curry and Anthony Veneziano both started regularly in the minors while Dax Fulton showed promise in that role before undergoing elbow surgery. Unless the Marlins spend to bring in a veteran, it should be an interesting competition.