Lakins was optioned to Triple-A Norfolk on Thursday.
Lakins was called up by Baltimore on Tuesday, and he allowed two runs on two hits and two walks while striking out two over two innings of relief during Wednesday's loss to the Cardinals. The right-hander has a 9.58 ERA in 10.1 innings over six major-league appearances this year and will head back to the minors after Denyi Reyes' contract was selected Thursday.