The Mariners reassigned Montes to minor-league camp Wednesday, Shannon Drayer of SeattleSports.com reports.
Montes impressed in his Cactus League opportunities, going 5-for-13 with a couple home runs. The 20-year-old has some of the biggest power in all of the minor leagues but will hope to make more contact after he struck out at nearly a 30 percent clip last season at High-A Everett.