Blas Castano

Organization Prospect Rankings

• 
  Ranked Seattle Mariners #23 prospect in 2025
  BA Grade/Risk: 40/Medium.
  
  Track Record: The Mariners acquired Castano at a steep discount, signing him in August 2023 after the Yankees released him from Double-A Somerset. Castano was originally a low-dollar sign by New York in 2018 out of the Dominican Republic. He has been solid if unspectacular at every level with the Yankees and Mariners, reaching Triple-A in both 2023 and 2024. Seattle added Castano to its 40-man roster in November.
  
  Scouting Report: Castano has both started and relieved throughout his career, and he always pitches out of the stretch. His repertoire is deep enough to start, with four pitches and weapons for hitters of either hand. His sinker sits 92-95 mph with plenty of armside run, and he will also mix in the occasional four-seamer up in the zone. Castano pairs it with a cutter that he likes to spot in on the hands of lefties. He also has a softer breaking ball, a sweeping slider, that he uses for whiff. He rounds out his arsenal with a firm changeup that is effective more for its late fade than for its velocity separation. His changeup will flash above-average at times and is the best of his secondaries when at its best. Castano is generally around the zone, and will show average command, with the ability to pitch backward at times. However, he will get cute around the edges, leading to slightly elevated walk rates.
  
  The Future: As a 40-man roster player, he will have multiple opportunities to contribute MLB innings in 2025. He is a jack-of-all-trades who is capable of starting, long relieving or one-inning stints. His ceiling is as a back-end starter, but his more likely outcome is as a do-everything swingman.
  
  Scouting Grades: Fastball: 55 | Slider: 50 | Changeup: 50 | Cutter: 50 | Control: 45.