Apr 11, 2019; Cincinnati, OH, USA; A view of a New Era Miami Marlins hat in the dugout during the game against the Cincinnati Reds at Great American Ball Park. Aaron Doster-Imagn Images

Marlins Top 20 Prospect Beginning to Turn Things Around in Arizona Fall League

Originally posted on Miami Marlins on SI
By Jeremy Trottier | Last updated Oct 29, 2025 1:00 PM ET

The Miami Marlins have a lot to look forward to when it comes to their long-term future as a franchise. They have put together quite an exciting roster of players who seem to be trending in the right direction of being competitive.

Now, the front office just needs to figure out which members of their team they want to retain as core pieces, and who they will elect to move on from in search of improvements heading into 2026.

Additionally, they have to meld that with the fact that their farm system is quite loaded with talent, and they are on the precipice of quite a few players being ready for their MLB debut.

A name who has started to really showcase some promising skills is pitcher Karson Milbrandt, a third-round pick from the 2023 MLB Draft by the Marlins, who has slowly but steadily worked his way through their farm system.

About Karson Milbrandt

Now, he is being given a chance in the Arizona Fall League, and despite a slow start, has really started to ramp up a bit recently. MLB.com writer Joe Trezza recently detailed some of the top performers from the AFL in week three of games, and among his top names was Miami's No. 18 prospect according to MLB Pipeline, Karson Milbrandt.

Sam Navarro-Imagn Images

In the aforementioned article from Joe Trezza, he had a promising update regarding Milbrandt and his production over the last week, stating the following about his pitching:

"The 21-year-old stands second on the Fall League strikeout leaderboard after a dominant performance, registering punchouts for seven of the eight outs he recorded in his latest effort for the Solar Sox. Milbrandt hasn't been untouchable this fall -- he's allowed five runs in three outings. But he's also racked up 18 strikeouts in 9 1/3 innings, an elite rate of missing bats."

Marlins righthander Karson Milbrandt used his AFL debut to show off his filthy cutter.

Batters came up empty 9 of the 15 times they swung at the pitch ⤵️ pic.twitter.com/dpaP39QS44
— Baseball America (@BaseballAmerica) October 10, 2025

This type of game is what the Marlins want to see from Milbrandt as he continues to try and build momentum off an extremely promising first few appearances in Double-A this year. Putting together a 1.69 ERA and 1.125 WHIP in Pensacola, he is now getting ever closer to a Triple-A promotion, which could come within the first few months of the 2026 season if he maintains the level of success he had this past year.

This fall, he has been getting some more work as a reliever, just to get him more reps, but adding him as either a starter or a long relief arm would be extremely valuable for Miami, especially the latter with a somewhat crowded rotation at the moment.

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