Baumann was recalled from Triple-A Norfolk on Saturday.
Baumann was sent down in late April, but he'll rejoin the active roster after posting a 3.72 ERA and 1.09 WHIP in 9.2 innings spanning four relief appearances in Norfolk. He logged a 6.14 ERA in 7.1 innings over five relief appearances in the majors early in the season, so he should pitch mainly in low-leverage situations.