Jack Flaherty has been okay this season. After a rough start, he seems to have bounced back and now finds himself in a position to either help the Cardinals drag themselves out of this mess or potentially be traded to another team. That being said, there are plenty of teams that could use some starting pitching. The Cardinals are one of them, but if they're out of contention, then there's really no reason to add anything major.
This is where Flaherty comes in. He owns a 4.15 ERA on the season but has been lights out since allowing 10 runs against the Angels. Teams like the Angels, Dodgers, and Red Sox could use some extra pitching, and Flaherty could get the Cardinals a decent haul from one of those teams.