Diamondbacks manager Torey Lovullo said Wednesday that Kelly (back) will throw a bullpen session Thursday, Nick Piecoro of The Arizona Republic reports.
Kelly came down with mid-back tightness shortly after camp opened, and as a result, will no longer start for the Diamondbacks on Opening Day. However, he has a chance to avoid the injured list and make a start in the second series of the season, and a return to the mound Thursday is a big step toward accomplishing that goal.