The A's placed Doolittle (oblique) on the 15-day disabled list Sunday, MLB.com's Jane Lee reports. The A's have not announced ow much time Doolittle is expected to miss with the setback, but it seems likely he will be given as much time as needed to get back to full strength by the postseason. No announcement about Doolittle's replacement has been made, but Luke Gregerson is the favorite to take over the closer's role for the A's.