The Seattle Seahawks handed the first bitter pill to the Kansas City Chiefs by breaking their 5-0 streak as the Chiefs lost 20-3 on Sunday night. While the Seahawks fans celebrated their win, after a two-game skid, they went bitter at their home baseball team, the Seattle Mariners. The Mariners opened the gates of their stadium, T-Mobile Park, to the Chiefs fans.

“This is so embarrassing,” wrote an account named Mariner Muse on X. “Sell the team.”

The comment came under a post where pictures from the Mariners stadium went viral before the Seattle vs. Kansas City face-off.

“Chiefs Party in the Mariners stadium. Gearing up for the game. Go Chiefs!” a Kansas City fan wrote, resharing pictures of the decked-up Mariners stadium with red, gold, and white balloons.

While hosting watch parties is a common practice during the season, the timing makes this situation different. The Mariners opened T-Mobile Park to Chiefs fans on the same night Kansas City was in Seattle to face the Seahawks in a Sunday Night Football game. By allowing a Super Bowl rival’s fans to use their facilities for a watch party during the matchup, the Mariners risked making it look like they were turning their backs on their own city’s NFL team.

This wasn’t simply a group of local Chiefs fans gathering to watch their team play in another city. The Chiefs were in Seattle, facing the Seahawks, and the Mariners’ stadium became a place for their fans to gather before the game. That helps explain why some Seahawks fans viewed the move as a betrayal.

The Mariners’ ballpark opened on July 15, 1999, after more than five years of planning and construction. Over the years, it has grown into one of the premier venues in Major League Baseball. The stadium was officially renamed T-Mobile Park in 2019 through a 25-year partnership with the hometown company.

For the Seattle community, the stadium holds a lot of emotion.

The Mariners marked 50 seasons of baseball by recognizing the franchise’s 50 Greatest Players at a pregame ceremony in August 2026 at T-Mobile Park. Even though it belongs mainly to the Mariners, it’s off-season in MLB, so they have hosted watch parties.

As found on their website, they have a dedicated section named ‘Pen Zone Pregame Party Schedule.’ They had a watch party on October 11 for the San Francisco 49ers face-off. The next one is on November 2, for the Chicago Bears clash.

There are more on November 8 vs. the Arizona Cardinals, on December 7 vs. the Dallas Cowboys, and on December 13 vs. the New York Giants.

The October 25th face-off against the Seahawks was a game away from home for the Chiefs that took place at Lumen Field. The stadium has a seating capacity of 68,740 fans. As reported by ESPN, the Seahawks vs. Chiefs face-off had full attendance for Sunday Night Football.

So, T-Mobile Park decided to host a watch party for the Kansas City fans who were away from home and could not get hold of a ticket for the matchday. Even though it was a heartwarming gesture, their day ended on a bitter note as the Seahawks left no stone unturned.

Patrick Mahomes threw for just 165 yards and was intercepted as the Chiefs struggled offensively. There was a lot of hype surrounding Kenneth Walker III, who joined Kansas City in the offseason after earning Super Bowl MVP honors with Seattle last season. But Seattle tamed that hype as he finished with only 36 yards on 14 rushing attempts.

The Chiefs found little to celebrate offensively, but Travis Kelce reached a career landmark with four catches. He now has 1,104 career receptions, moving past Marvin Harrison (1,102) and Cris Carter (1,101) to claim fifth place on the NFL’s all-time list.

“Playing a team like Kansas City and all the killers that they got on that side, we knew how big this game was, and we wanted this one badly,” said Jaxon Smith-Njigba, the NFL’s leading receiver and reigning Offensive Player of the Year. “You know, we saw it as a playoff game.”

While the Seahawks fans will remember this victory over the undefeated Chiefs for a long time now, the Mariners’ behavior left a deep wound in their hearts.

“Wait..the Mariners rented out T-Mobile for Chiefs fans,” a fan wrote.

“@Mariners seriously? Have some pride in your city,” wrote a fan.

“@TMobilePark @Mariners this is atrocious. Renting out to the enemy? 😱” another fan wrote.

“@Kevin_Martinez what the hell bro,” read another comment.

“This is pathetic! Show some respect, @Mariners,” a fan wrote.

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