Former Seattle Mariners bullpen standout Erik Swanson is hanging up his cleats.

The 32-year-old Swanson announced his retirement from MLB on Thursday.

M’s announce date, giveaway for Randy Johnson number retirement

“My time in this game was nothing short of amazing,” Swanson wrote in a post on Instagram. “Thank you to everyone who helped me along the way and to all those who supported me. You all have truly made this journey an unforgettable 12 years.”

Swanson played four of his seven MLB seasons with the Mariners, including his best campaign in the big leagues. That was 2022 when the 6-foot-3 right-hander emerged as a reliable option to get left-handed hitters out with a strong splitter.

Swanson made 57 appearances during the 2022 regular season and finished with career-best marks in ERA (1.68), WHIP (0.913), FIP (0.913) and fWAR (1.7). He also made three scoreless, hitless appearances out of the bullpen in the 2022 postseason for Seattle.

The Mariners traded Swanson and minor league pitcher Adam Macko to the Toronto Blue Jays for outfielder Teoscar Hernández in November 2022.

Swanson continued to be effective in his first season with Toronto, posting a 2.97 ERA, 1.095 WHIP and 1.5 fWAR in a career-high 69 appearances in 2023, but his production fell off in 2024 and 2025. He was released by the Blue Jays in June.

Swanson missed time during spring training in 2024 after his four-year-old son Toby was hit by a car. Toby Swanson made a full recovery.

Swanson was included in multiple trades centered around star players during his career. Drafted in the eighth round in 2014 by the Texas Rangers, he went to the New York Yankees in a 2016 deal that sent Carlos Beltrán to Texas. And in 2018, he was one of three prospects dealt from the Yankees to the Mariners for starting pitcher James Paxton.

He made his MLB debut in 2019 with Seattle and started eight games that season, but he spent the majority of his time in the big leagues as a reliever.

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