Cardinals Have Golden Opportunity to Claim Mariners' Casey Legumina

The St. Louis Cardinals should place a waiver claim quickly on the former Seattle Mariners hurler.

Apr 14, 2026; San Diego, California, USA; Seattle Mariners relief pitcher Casey Legumina (64) throws a pitch during the eighth inning against the San Diego Padres at Petco Park. Mandatory Credit: David Frerker-Imagn Images | David Frerker-Imagn Images

The St. Louis Cardinals have one of the best overall records in Major League Baseball, but that doesn't mean that everything is sunshine and rainbows for the organization.

Right now, there are just four teams in Major League Baseball with more wins than the Cardinals' 14. Those four teams are the Los Angeles Dodgers (16), San Diego Padres (16), Cincinnati Reds (16), and the Atlanta Braves (16). The Cardinals are right there among the league's best, but the bullpen needs a boost. St. Louis' bullpen is ranked 25th in baseball with a 5.34 ERA so far this season.

We've broken down the bullpen struggles multiple times already this season already. It's a big story and is something that realistically should be spoken about more. Riley O'Brien looks like the second-best reliever in the National League, behind just Mason Miller of the San Diego Padres. JoJo Romero and Gordon Graceffo have both been lights-out. George Soriano has been solid, but had one bad outing on April 18 when he allowed three earned runs.

The Cardinals Should Claim The Mariners Hurler

Apr 14, 2026; San Diego, California, USA; Seattle Mariners relief pitcher Casey Legumina (64) throws a pitch during the eighth inning against the San Diego Padres at Petco Park. Mandatory Credit: David Frerker-Imagn Images | David Frerker-Imagn Images

Outside of these four, the rest of the group has simply struggled. Because of that, it wouldn't hurt to add another arm to the mix and see if they can find something. That doesn't mean that the Cardinals should go out and make some massive trade or something along those lines. Instead, the Cardinals should shop around the edges and see if they can find a diamond in the rough. That's where Seattle Mariners hurler Casey Legumina should come into play. Daniel Kramer of MLB.com reported that Legumina would be designated for assignment.

It's not as if Legumina is having a big year so far. If he was, then the Mariners wouldn't have designated him for assignment. He has pitched in eight games so far this season and has a 4.63 ERA in 11 2/3 innings of work. Last year, he had a 5.62 ERA in 48 appearances in his first extended time in the big leagues. Overall, he has appeared in 73 games in his big league career and has a 5.83 ERA. Again, the numbers don't jump off the page. But he is 28 years old and the advanced metrics are a bit better.

Right now, he's in the 84th percentile in walk rate and 78th percentile in extension. In 2025, he was in the 77th percentile in expected batting average against at .218. He was also in the 70th percentile in strikeout rate and 58th percentile in expected ERA at 3.82. He finished the season at 5.62, but that shows there was some bad luck mixed in. Even this season, he has been unlucky. He has a 4.63 ERA but a 3.14 FIP. That's a sign of bad defense behind him.

For the Cardinals, they play great defense. Legumina is young and the underlying numbers tell a different story than his 5.83 career ERA. St. Louis should act quickly and place a waiver claim.