The St. Louis Cardinals upgraded their bullpen at the trade deadline by bringing in reliever Shawn Armstrong in a deal that sent Dylan Carlson to the Tampa Bay Rays. The Cardinals were buyers at the deadline with the hope of making a playoff push over the second half of the season.

In a bit of a head scratching move, St. Louis designated Armstrong for assignment on Tuesday, according to The Athletic’s Katie Woo. The team will replace the 10-year veteran with righty reliever Riley O’Brien.

Armstrong is a journeyman relief pitcher but he performed admirably during his brief time with the Cardinals. Since joining the team at the beginning of August, Armstrong is 1-0 with a 2.84 ERA, 1.026 WHIP and 12 strikeouts in 12.2 innings. He posted a stellar 153 ERA+, albeit in a small sample size.

The 32-year-old righty made his first appearance for St. Louis on August 2. Things got off to a bit of a rocky start as he gave up four earned runs in his next 4.1 innings. However, Armstrong was excellent over his next seven appearances, holding opponents scoreless and striking out six batters in 6.2 innings. The Cardinals called on him in back-to-back games Sunday and Monday and he delivered two scoreless frames.

The Cardinals DFA’d recently acquired reliever Shawn Armstrong

Aug 5, 2024; St. Louis, Missouri, USA; St. Louis Cardinals relief pitcher Shawn Armstrong (30) pitches against the New York Mets during the sixth inning at Busch Stadium.
Jeff Curry-USA TODAY Sports

St. Louis’ bullpen has been all over the place this season. Led by Reliever of the Year candidate Ryan Helsley, the group ranks top 13 in ERA, saves, walks per nine innings, batting average against and WHIP. However, Cardinals relievers are 21st or worse in holds, strikeout percentage, WPA and fWAR and they’re dead last in strikeouts and K/9.

Losing Armstrong makes the bullpen weaker. But releasing him less than a month after acquiring him is even stranger when you consider that the team gave up Dylan Carlson to land Armstrong. Carlson was selected in the first round of the 2016 draft by the Cardinals. He became one of the top prospects in the minors before debuting for St. Louis in 2020. The following season, Carlson finished third in Rookie of the Year voting.

Despite being a game under .500 entering play on Tuesday and 10.5 games behind the first-place Milwaukee Brewers in the NL Central, the Cardinals appeared determined to make a postseason push. Starting pitcher Miles Mikolas recently stated that St. Louis could win 17 straight games if necessary and the team impressed Brewers’ manager Pat Murphy with their scrappy play.

However, the team has gone just 15-20 since returning from the All-Star break. And while the Cardinals are only six games back in the National League Wild Card race, they’d have to overtake four teams to grab the final playoff berth. St. Louis has just a 1.3 percent chance of making the postseason according to baseball-reference.com. Making matters even worse, the Cardinals lost All-Star catcher Willson Contreras to a broken finger that will keep him sidelined until late September.

Armstrong is playing this season on a one-year, $2.05 million contract. With his release by St. Louis, he’ll hit waivers and if he’s claimed before September he will be eligible to pitch in the postseason for his new team.