Lowther was recalled from Triple-A Norfolk on Sunday.
Lowther was recalled by the Orioles on Wednesday and then sent back to Norfolk on Thursday without making an appearance with the big club. He'll rejoin Baltimore ahead of their game against Cleveland on Saturday and figures to be able to pitch in long relief if needed. John Means (shoulder) was placed on the 10-day injured list in a corresponding roster move. Lowther could be a candidate to take Means' spot in the rotation while the left-hander recovers.