The Orioles activated McDermott from the bereavement list and placed him on the 15-day injured list Tuesday due to back discomfort.
McDermott's season is over after the 27-year-old right-hander posted an ugly 15.58 ERA, 2.77 WHIP and 9:12 K:BB across 8.2 innings for Baltimore this season. He served up three home runs and 15 earned runs in his limited work.