MINNEAPOLIS -- The Twins declined reliever Sergio Romo's club option for 2021 on Wednesday, sources told MLB.com, adding the well-liked veteran to the cascade of key contributors who officially became free agents following the conclusion of the World Series. The team has not confirmed the news.

The club option was worth $5 million, and the Twins will instead pay a $250,000 buyout. Minnesota doesn't have any other major option decisions ahead of Sunday's deadline.

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Romo, 37, was a key late-inning piece of the Twins bullpens that ranked among the best in the American League during the runs to back-to-back American League Central championships in 2019 and '20, the club's first division titles since 2010. He had a 3.59 ERA and eight saves in 51 games across parts of two seasons in Minnesota, often holding down the eighth or sometimes ninth inning throughout his Twins tenure.

Romo quickly became a fan favorite in his short time in Minnesota and energized his teammates around the clubhouse, including with the loud blaring of "El Mechón" on the stadium speakers as his entrance music that Twins relievers would dance to in the bullpen.

After the veteran slider specialist posted a 3.18 ERA in 2019 following his acquisition with Minor League right-hander Chris Vallimont from Miami at the Trade Deadline in exchange for prospect Lewin Díaz, Romo took a step back to a 4.05 ERA in 24 appearances this season with the second-highest walk rate of his career.

He allowed three unearned runs in two-thirds of an inning and took the loss in Game 1 of the 2020 Wild Card Series against the Astros.

Ehire Adrianza, Alex Avila, Tyler Clippard, Nelson Cruz, Marwin Gonzalez, Rich Hill, Trevor May and Jake Odorizzi also became free agents on Wednesday, leaving several holes for the Twins to fill in their bullpen this offseason.

Romo, Clippard and May were three of manager Rocco Baldelli's most trusted arms this season, and the club could lean more heavily on Cody Stashak, Matt Wisler and Jorge Alcala in 2021 while younger options like Edwar Colina establish themselves in the Majors. Caleb Thielbar also emerged as a surprise success story in his second go-around in the Twins' organization.