Brothers spent much of the previous four seasons with the Rockies. The left-hander was 4-1 with three saves and a 4.71 ERA in 32 appearances with Albuquerque this season.
Lefty Aaron Laffey was designated for assignment on Saturday to make room for Brothers on the roster.
Laffey was with the Rockies for just one day. He got the win pitching in relief Friday night despite allowing a three-run homer in Colorado's 5-3 victory over the Braves.
It was Laffey's first major league appearance since April 26, 2013, and first win since Sept. 25, 2012.