Kelly, who was placed on the COVID-19 injured list Sunday, is symptomatic, Nick Piecoro of The Arizona Republic reports.
Arizona manager Torey Lovullo said Kelly is "grinding through some of these tough early days" of the illness. This sets a potential return date in limbo, leaving the projected rotation uncertain. Luke Weaver (shoulder) will be making a minor-league rehab start Friday, so a return to the rotation for Caleb Smith or a fill-in start for Matt Peacock may be the stop-gap measure.