The Orioles reinstated left-hander Zach Britton from the 10-day disabled list on Tuesday.
Britton, the team's closer, has been sidelined since April 18 with a left forearm strain. He allowed one hit in a scoreless inning against the Red Sox on Tuesday.
Britton made two rehab appearances in Double-A with the Bowie Baysox.
On Friday, he acknowledged having "a little hesitation" and was unable to get out of the inning, throwing 28 pitches in two-thirds of an inning, allowing two walks and a solo home run.
On Sunday, he retired the side on 11 pitches, allowing a hit and striking out one.
To compensate for the move, the Orioles optioned RHP Mike Wright to Triple-A Norfolk.