News, Tacoma Rainiers

Tacoma Rainiers Sign Professional Development License, Extend Seattle Mariners Affiliation

TACOMA, WA – The Seattle Mariners, in conjunction with Major League Baseball (MLB), announced today that the Tacoma Rainiers will continue operating as Seattle’s Triple-A affiliate under a new Professional Development License (PDL) for the 2021 season. This year marks the 27th that the organizations have been affiliated dating back to 1995, and the upcoming season will be the first within MLB’s new player development system.

“We’re thrilled to extend our partnership with the Seattle Mariners and Major League Baseball while continuing to provide an excellent fan experience and creatively support our community,” said Tacoma Rainiers President Aaron Artman. “We’re excited to get back to Rainiers baseball in 2021.”

Tacoma will compete in the 10-team Triple-A West and will be aligned in the west division with the Las Vegas Aviators (OAK), Reno Aces (ARI), Sacramento River Cats (SF), and Salt Lake Bees (LAA). The east division consists of the Albuquerque Isotopes (COL), El Paso Chihuahuas (SD), Oklahoma City Dodgers (LAD), Round Rock Express (TEX) and Sugar Land Skeeters (HOU).

The Rainiers are one of four teams who were extended an affiliate invitation by the Mariners on Dec. 9. The other Seattle affiliates for 2021 include the Arkansas Travelers (Double-A), Everett AquaSox (High-A) and Modesto Nuts (Low-A).

The Mariners announced the 2021 Triple-A coaching staff on January 27. Kristopher Negrón, a 2019 Tacoma infielder and 14-year professional player, will make his managerial debut with the Rainiers after serving as Seattle’s Assistant to Director of Player Development in 2020. Negrón will be joined by returning hitting coach Roy Howell, pitching coach Rob Marcello Jr. and Eric Young Jr., who also played with Tacoma in 2019.

“The partnership between Seattle and Tacoma is a perfect setup,” Negrón said. “Tacoma is a great city, and so are its fans and Cheney Stadium’s facilities. Being so close to T-Mobile Park makes this a highly beneficial affiliation.”

Tacoma will be the highest level affiliate for a Mariners player development system that ranks second according to Baseball America, and boasts six of the Top 100 Baseball Prospects according to MLB Pipeline. All six prospects participated in Seattle’s 2020 Alternate Training Site at Cheney Stadium, including the organization’s top prospect, OF Jarred Kelenic (No. 4 overall prospect by MLB Pipeline), OF Julio Rodriguez (5), RHP Emerson Hancock (31), RHP Logan Gilbert (33), RHP George Kirby (92) and OF Taylor Trammell (100).

About the Tacoma Rainiers

The Tacoma Rainiers are the Triple-A affiliate of the Seattle Mariners. Tacoma has been a member of the Pacific Coast League since Cheney Stadium opened in 1960, and has been a Mariners affiliate since establishing the Rainiers moniker in 1995.

The most up-to-date news and notes about the Tacoma Rainiers and Cheney Stadium can be found at, or by following the Rainiers on Twitter (@RainiersLand), Instagram (@tacomarainiers) and liking the team on Facebook.

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