Drake, a 43rd-round pick out of the Naval Academy in 2008, was 11-8 with a 3.32 ERA in 27 games at Triple-A Norfolk, Double-A Bowie and Single-A Frederick. He walked 43 and struck out 129 in 162 2/3 innings.
Most of his success came with the Keys, where he went 8-3 with a 2.14 ERA.
The 40-man roster currently stands at 39. The Orioles can't add anyone else from within the organization before the Rule 5 draft.
Among the minor leaguers who will be exposed to the draft are position players Buck Britton, Tyler Henson, John Hester, Caleb Joseph, Greg Miclat, Billy Rowell, Brandon Waring, Ronnie Welty and Robbie Widlansky, and pitchers Tim Bascom, Brandon Cooney, Pat Egan, Eddie Gamboa, Sean Gleason, Steve Johnson, Cole McCurry, Wynn Pelzer and Rick Zagone.
Bascom was named the organization's minor league Pitcher of the Year in 2011.
Last winter, the Orioles lost reliever Pedro Beato to the Mets. The Brewers selected Egan, but they offered him back to the Orioles.
NOTE: The Orioles have agreed to terms with infielder Matt Antonelli, a former first-round pick of the Padres who spent last season at Triple-A Syracuse. He could compete for a utility job. Check Steve Melewski's blog for more information.