To fill his roster spot, Baltimore recalled left-hander Donnie Hart, who presumably will be sent back to Triple-A Norfolk when Valencia returns.
Britton to throw again Saturday
While the Orioles continue to monitor the forecasts at their affiliates, the plan for now is to have Zach Britton continue his rehab this weekend with Norfolk. Britton was originally slated to throw for the Tides earlier this week, but a poor weather forecast shifted Wednesday's rehab debut to Class A Advanced Frederick instead.
Britton struck out three in Wilmington in his debut and got positive reports.
"I wasn't expecting him to be that crisp and that sharp," manager Buck Showalter said of Britton, who is rehabbing from offseason Achilles surgery. "I don't know if it was intentional that he came in against three left-handed hitters … but a good start. Couldn't ask for more. We will take a look at the weather, see where it fits in the schedule."
Britton is expected to return in early June if he remains on schedule.
Showalter also said Darren O'Day (right elbow) is feeling better, but the right-hander will have to pitch on a rehab assignment before he can be activated from the disabled list.