Even if the Cardinals' weren't in last place in the NL Central, Jack Flaherty probably would have been available on the trade market. Flaherty is only making $5.4 million this season and is set to become a free agent after the 2023 season ends. While his work early in his career seemed to be setting him up for a contract extension with St. Louis, his recent injury history and production put a damper on those aspirations.
There are some issues here, though. St. Louis is certainly selling at the trade deadline, but it seems like they have specific types of returns they are looking for. Given Flaherty's issues in recent years and the fact that he is about to hit free agency, he may not bring back the near major league ready talent that the Cardinals are seeking. It won't help the demand for his services that his strikeout rate and walk rate have been trending in the wrong direction along with the fact that it sounds like Flaherty has blamed his catcher at least partially for his woes in 2023.
At the end of the day, it is still likely that Flaherty gets moved. He hasn't been good enough to give a qualifying offer and with the Cardinals out of it, moving him still remains the best option. He just probably won't bring back the return the Cardinals would have hoped.
The easiest players to move at the trade deadline are relievers that are performing well, aren't making a lot of money, and who are about about to be free agents. Chris Stratton fits that mold to a T as his 2.99 FIP in 2023 is stellar thanks to a much improved walk rate, he is making just $2.8 million in 2023, and will hit free agency after the 2023 season.
While Stratton has had stretches where he was hit harder than one would like, the rest of his Statcast profile looks very promising. There isn't a contender out there that doesn't want to at least entertain upgrading their bullpen and St. Louis is going to be taking a lot of calls about Stratton as a result. He is as good as gone.