Danner was placed on the 15-day injured list with a left oblique strain Saturday, Kaitlyn McGrath of The Athletic reports.
Danner made his big-league debut in relief against the Cubs on Friday but retired just one batter before exiting with discomfort in his left side. His diagnosis has since been upgraded to a strain, so he'll sit for at least the next two weeks. Nate Pearson will take his place on the roster.