Baumann was recalled from Triple-A Norfolk on Tuesday, Nathan Ruiz of The Baltimore Sun reports.
Baumann is one of the top pitching prospects in the Orioles organization, and he'll join the major-league roster for the first time following an effective showing at the Triple-A level. The righty was promoted to Norfolk at the end of July and posted a 2.00 ERA and 1.15 WHIP in 27 innings across six starts. Baumann has worked exclusively as a starter this year, but the Orioles haven't yet announced whether he'll begin his major-league career as a starter or reliever.