What happened: Corbin Burnes returned Tuesday, followed by Zac Gallen and Michael Soroka on Wednesday. The initial plan paired Gallen's start with Soroka in relief, drawing on Soroka's bullpen experience. [Arizona Sports](https://arizonasports.com/mlb/arizona-diamondbacks/zac-gallen-michael-soroka-reinstated-ahead-of-d-backs-return-wednesday).
Why it matters: Returning starters create competition for innings, but workload restrictions can preserve opportunities for other pitchers. For Kelly, the immediate implication is competition for assignments rather than an established role change.
By the numbers: Entering their September 9 returns, Soroka had a 3.40 ERA across 95⅓ innings in 2026; Gallen had a 6.34 ERA across 98 innings, a 2.94-run gap. [Arizona Sports](https://arizonasports.com/mlb/arizona-diamondbacks/zac-gallen-michael-soroka-reinstated-ahead-of-d-backs-return-wednesday).
What to watch: The next rotation assignments will show whether Kelly continues starting or shifts to another role.