Steven Matz will start the season in St. Louis.
For a small portion of the offseason, there were rumors that Steven Matz could be traded. After signing three starting pitchers in Lance Lynn, Kyle Gibson, and Sonny Gray, John Mozeliak was awarded some flexibility with trades. A departure of Steven Matz would have removed some uncertainty in health from the starting rotation, and it could have cleared up some space financially given Matz's remaining $24 million on his contract.
However, as the trade market for starting pitchers begins to cool down, and after the Tyler Glasnow blockbuster trade to the Los Angeles Dodgers, it seems more likely that Steven Matz will start 2024 in the St. Louis Cardinals' rotation.
Matz is actually a good starting pitcher...when he's healthy. That's the main issue when it comes to his viability in the 2024 rotation. He has yet to pitch more than 160 innings in a season, and he only pitched 105 innings last year, although eight of his twenty-five appearances were out of the bullpen, thus sacrificing some of his potential innings total.
Given a fully healthy season (160+ innings), Steven Matz could be a 3.0-WAR player, good enough for a #2 or #3 on most staffs. He carries pretty decent injury risks, but his twenty-five appearances last year could be a sign of improving health. It is likely that the Cardinals hold onto Steven Matz for next year. That could change if the season goes awry again, however.