Arroyo will begin transitioning from second base to left field this month during the Columbian Winter League, Adam Jude of the Seattle Times reports.
Arroyo played second base exclusively in 2025 between High-A Everett and Double-A Arkansas, slashing .262/.401/.433 with 17 homers and 12 steals between the two stops. He has never played the outfield before, but with the Mariners' infield depth, the organization has elected to move the 21-year-old to left field. Arroyo could push to debut at some point during the 2026 season.