Anthony Mazur Flashes Potential in Spot Start for Marlins

The Miami Marlins didn't necessarily need Anthony Mazur to dominate the Phillies on Wednesday night–they just needed him to eat innings. But what they got instead was a glimpse into why he was such a key piece in last year's Luiz Arraez trade, and why the front office remains high on the 24-year-old right-hander.

In just the ninth start of his big-league career, Mazur delivered 5 2/3 innings against one of the National League’s most dangerous lineups, allowing five hits and four earned runs in a 4-2 loss for the Marlins. He walked four, struck out five, and threw 97 pitches—59 for strikes. While far from flawless, the outing was a welcome sight for a Marlins team that’s been scrambling to fill innings amid a season plagued by injuries. Simply getting a starter into the sixth felt like a small win.

Mazur became the fifth player acquired by Peter Bendix at last season’s trade deadline to make his Marlins debut, joining Connor Norby, Kyle Stowers, Graham Pauley, and Agustin Ramirez.

A Competitive Slider Shows Why Marlins Believe in Mazur's Ceiling

What stood out most from Mazur's night wasn't his stat line–it was his pitch movement. Four of his five strikeouts came via his sharp, late-breaking slider that Phillies hitters couldn't square up. The pitch consistently induced weak contact and generated six whiffs, either ending at-bats or setting up outs later in the count.

Mazur’s raw tools were on full display. His fastball sat comfortably between 93–95 mph and touched 96, showing strong carry at the top of the zone. His slider, ranging from the mid to upper 80s, featured sharp downward break and tight spin. When working ahead in the count (66.7% first pitch strikes), Mazur pitched with noticeable confidence and competitiveness.

As is often the case with young starters, command proved to be Mazur’s biggest challenge. His four walks extended innings and gave the Phillies a prime opportunity to break the game open in the fourth. J.T. Realmuto capitalized with an RBI single, followed by a three-run homer to center field from Bryson Stott that effectively put the game out of reach.

Still considering the context, the outing was more than encouraging. Mazur was called upon for a spot start in a battered rotation, facing a playoff-caliber lineup, and somehow managed to keep his team in the game.

A Building Block for the Future

Miami's front office didn't trade away a fan favorite like Arraez last season without firm belief in what they were getting in return. While many eyes remain fixed on top prospects like Dillon Head and Jakob Marsee, it's Mazur who may end up being the most MLB-ready of the group.

If he can rein in the walks, there's a legitimate back-end starter in there. His stuff is already big-league caliber, even though he will likely return to the minors for now, but he left a strong impression. For a Marlins club desperate for rotation depth and future building blocks, Wednesday night offered something they haven't had much of this season: a reason to keep trusting the process.