The Cardinals acquired Cijntje from the Mariners on Monday as part of a three-team trade involving the Rays, Joel Sherman of the New York Post reports.
St. Louis also receives Tai Peete, Colton Ledbetter and a compensatory draft pick. Brendan Donovan is going to Seattle and Ben Williamson is headed to Tampa Bay as part of the deal. A first-round pick in the 2024 Draft, Cijntje held a 3.99 ERA and 120:51 K:BB over 108.1 innings between High-A Everett and Double-A Arkansas in 2025. The Mariners said over the weekend that Cijntje -- who has been a switch pitcher -- would focus on throwing right-handed in spring training. It's unclear whether the Cardinals will also have the same plan or have Cijntje continue switch pitching.