Mariners Designate RHP Jackson Kowar for Assignment

The Seattle Mariners have designated right-handed pitcher Jackson Kowar for assignment to clear a 40-man roster spot for catcher Jhonny Pereda. Kowar, who returned in May 2025 after Tommy John surgery in March 2024, pitched 17 low-leverage innings for the Mariners. Despite glimpses of his potential, his lack of minor league options and a 21.1% strikeout rate contributed to the decision. The Mariners may still attempt to outright him to retain him in the organization.