Seattle Mariners outfielder Lazaro Montes poses for a portrait during media day at Peoria Sports Complex on Feb. 20. Mark J. Rebilas-Imagn Images

One Seattle Mariners Affiliate Has Already Clinched a Spot in MiLB Championship Series

Originally posted on Minor League Baseball on SI
By Brady Farkas | Last updated Jun 20, 2025 2:18 PM ET

Congratulations are in order for the Everett AquaSox, the High-A affiliate of the Seattle Mariners. The AquaSox defeated the Spokane Indians 8-3 on Thursday night, solidifying themselves as the first-half champions of the Northwest League.

As a result, the AquaSox have already clinched a spot in the Northwest League championship series, set for later this summer.

The following comes from the official Minor League Baseball website:

However, with only six clubs in the Northwest League, the format for the Postseason will consist of a single, best-of-five Championship series. The two playoff participants will be decided based on the best winning percentage of each half. In the event the same Club wins both halves, the Club with the next best winning percentage in the second half will advance.

The happy totals from tonight in Spokane. pic.twitter.com/ouMkBP6Ohl
— Everett AquaSox (@EverettAquaSox) June 20, 2025

The AquaSox are one of the most loaded rosters in the entire minor league system, complete with five Top-100 prospects. Jonny Farmelo is currently hurt, but Lazaro Montes, Colt Emerson, Jurrangelo Cijtnje and Michael Arroyo are all integral parts of the roster, and important parts of the M's future.

It seems unlikely that Emerson, Montes or Arroyo will make it to the championship series, as they are most likely nearing a Double-A promotion. However, Farmelo could stay in Everett in order to get himself some more developmental time once he returns from a rib injury. Cijntje, who is in his first professional season, could potentially stay in Everett also, anchoring the staff.

The Mariners have nine Top-100 prospects in their system. In addition to these five, Ryan Sloan and Felnin Celesten (Modesto), are joined by Cole Young (MLB) and Harry Ford (Tacoma).

This article first appeared on Minor League Baseball on SI and was syndicated with permission.

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