The 27-year-old Brach had a 3.19 ERA in 33 games last season with the Padres, striking out 31 in 31 innings. In three seasons with San Diego, Brach went 3-6 with a 3.70 ERA over 109 appearances.
San Diego gets right-hander Devin Jones in Monday's trade. The 23-year-old Jones was 5-7 with a 5.64 ERA in 25 starts this year with Class A Frederick and Double-A Bowie.
Jones was selected by Baltimore in the ninth round of the 2011 amateur draft out of Mississippi State.