Kansas City Royals Brad Keller
Brad Keller has been with the Royals for the past 6 seasons and he has had an inconsistent career so far. Keller had a very solid rookie season in 2018 and was superb in the shortened 2020 year, however in '21 and '22 he had a 5.24 era in 61 games ( 48 starts ). The problem with Keller so far this season is throwing strikes, as of May 16, he leads all of baseball in walks with 40 in 43.1 innings.
He will need to limit free passes to up his potential trade stock, which could rise because he could be an unrestricted free agent after this season if the Royals don't extend him. Some other facts that may not make Keller a fit in St. Louis are he doesn't fill the need of having a swing-and-miss starter. Jack Flaherty could become that guy again, but the Cardinals have been rock bottom in the league in K's the last few seasons and it could be a field the Cardinals will look to help fill.
But what Brad Keller has been in the big leagues is an innings eater, he has averaged 176 innings a season since 2018 which always adds value. He is a long shot right now, especially if he doesn't stop walking a batter an inning. However he will be 28 at the end of this season, still very young and he has shown production in parts of his career, the upside could be something to go after.