The 29-year-old southpaw had been on a rehabilitation assignment.
A third-round pick of the Orioles in 2006, Britton was a perfect 47-for-47 in save opportunities last year, when he finished fourth in American League Cy Young voting. On April 14 he recorded his 54th consecutive save, tying Tom Gordon for the second-longest streak in MLB history.
Two days later, Britton landed on the disabled list with a forearm strain. He returned on April 28 and made two appearances before going back on the disabled list.