Mariners move Lazaro Montes and Michael Arroyo to Triple-A Tacoma

The Seattle Mariners have promoted two of their highest-upside position players, sending outfielder Lazaro Montes and infielder/outfielder Michael Arroyo to Triple-A Tacoma, according to reports from. The club had not confirmed the moves at the time of publication, but the timing fits the kind of midseason progression Seattle has used in recent years for prospects approaching the majors.

Montes, widely viewed as the Mariners’ most prominent bat in their system, is stepping into Tacoma after producing at Double-A Arkansas. In 79 games this season, the 21-year-old posted a.234 batting average with a.369 on-base percentage and a.550 slugging mark. His 25 home runs led all hitters in the Mariners’ farm system, and his power surge has continued into recent form, including a June line of.299 with a 1.199 OPS.

The Mariners’ decision to push Montes forward is also tied to how his profile has translated across multiple levels. MLB Pipeline ranks him as the Mariners’ top hitting prospect, including No. 26 overall among prospects, and the organization’s internal pecking order has shifted as other top names advanced. reported Montes took over as Seattle’s No. 1 hitting prospect when Colt Emerson graduated, with Kade Anderson and Ryan Sloan ahead of him in the broader organizational ranking. His total power has been a consistent thread, as he has reached 101 home runs across five Minor League seasons.

Montes’ path has been accelerated by a track record of success and repeat promotions. He signed with the Mariners out of Havana in 2022 for $2.5 million as a 17-year-old international signee and, according to, he has been promoted each of the past four summers. That pace has been backed by award runs as well, including Northwest League MVP honors in 2025 and California League MVP honors in 2024, building expectations that his skill set can play against more advanced pitching.

Arroyo, the other reported mover, is following a parallel midseason pattern after his work at Arkansas. reported that in 65 games this season he hit.287 with an.820 OPS. His versatility has been a key part of his development, with time this year split between second base and left field. That matters for Seattle because it impacts the options available for how Arroyo could be used as he climbs, particularly once he is competing against Triple-A pitching and against more specific defensive assignments.

The Mariners already have other prospects carving out roles on the infield and around the diamond, which could shape Arroyo’s path. noted Emerson is in Seattle’s long-term plans and performing well enough to take ground work off the organizational chart, while Cole Young has been developing at second base. Felnin Celesten has been developing as a shortstop at High-A, leaving Arroyo to build his case through both bat and positional flexibility as he reaches Tacoma.